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65f3c785 | 1 | .TH fio 1 "October 2013" "User Manual" |
d60e92d1 AC |
2 | .SH NAME |
3 | fio \- flexible I/O tester | |
4 | .SH SYNOPSIS | |
5 | .B fio | |
6 | [\fIoptions\fR] [\fIjobfile\fR]... | |
7 | .SH DESCRIPTION | |
8 | .B fio | |
9 | is a tool that will spawn a number of threads or processes doing a | |
10 | particular type of I/O action as specified by the user. | |
11 | The typical use of fio is to write a job file matching the I/O load | |
12 | one wants to simulate. | |
13 | .SH OPTIONS | |
14 | .TP | |
49da1240 JA |
15 | .BI \-\-debug \fR=\fPtype |
16 | Enable verbose tracing of various fio actions. May be `all' for all types | |
17 | or individual types separated by a comma (eg \-\-debug=io,file). `help' will | |
18 | list all available tracing options. | |
19 | .TP | |
d60e92d1 AC |
20 | .BI \-\-output \fR=\fPfilename |
21 | Write output to \fIfilename\fR. | |
22 | .TP | |
b2cecdc2 | 23 | .BI \-\-runtime \fR=\fPruntime |
24 | Limit run time to \fIruntime\fR seconds. | |
d60e92d1 AC |
25 | .TP |
26 | .B \-\-latency\-log | |
27 | Generate per-job latency logs. | |
28 | .TP | |
29 | .B \-\-bandwidth\-log | |
30 | Generate per-job bandwidth logs. | |
31 | .TP | |
32 | .B \-\-minimal | |
d1429b5c | 33 | Print statistics in a terse, semicolon-delimited format. |
d60e92d1 | 34 | .TP |
49da1240 JA |
35 | .B \-\-version |
36 | Display version information and exit. | |
37 | .TP | |
065248bf | 38 | .BI \-\-terse\-version \fR=\fPversion |
4d658652 | 39 | Set terse version output format (Current version 3, or older version 2). |
49da1240 JA |
40 | .TP |
41 | .B \-\-help | |
42 | Display usage information and exit. | |
43 | .TP | |
44 | .BI \-\-cmdhelp \fR=\fPcommand | |
45 | Print help information for \fIcommand\fR. May be `all' for all commands. | |
46 | .TP | |
de890a1e SL |
47 | .BI \-\-enghelp \fR=\fPioengine[,command] |
48 | List all commands defined by \fIioengine\fR, or print help for \fIcommand\fR defined by \fIioengine\fR. | |
49 | .TP | |
d60e92d1 AC |
50 | .BI \-\-showcmd \fR=\fPjobfile |
51 | Convert \fIjobfile\fR to a set of command-line options. | |
52 | .TP | |
d60e92d1 AC |
53 | .BI \-\-eta \fR=\fPwhen |
54 | Specifies when real-time ETA estimate should be printed. \fIwhen\fR may | |
55 | be one of `always', `never' or `auto'. | |
56 | .TP | |
30b5d57f JA |
57 | .BI \-\-eta\-newline \fR=\fPtime |
58 | Force an ETA newline for every `time` period passed. | |
59 | .TP | |
60 | .BI \-\-status\-interval \fR=\fPtime | |
61 | Report full output status every `time` period passed. | |
62 | .TP | |
49da1240 JA |
63 | .BI \-\-readonly |
64 | Turn on safety read-only checks, preventing any attempted write. | |
65 | .TP | |
c0a5d35e | 66 | .BI \-\-section \fR=\fPsec |
49da1240 | 67 | Only run section \fIsec\fR from job file. Multiple of these options can be given, adding more sections to run. |
c0a5d35e | 68 | .TP |
49da1240 JA |
69 | .BI \-\-alloc\-size \fR=\fPkb |
70 | Set the internal smalloc pool size to \fIkb\fP kilobytes. | |
d60e92d1 | 71 | .TP |
49da1240 JA |
72 | .BI \-\-warnings\-fatal |
73 | All fio parser warnings are fatal, causing fio to exit with an error. | |
9183788d | 74 | .TP |
49da1240 | 75 | .BI \-\-max\-jobs \fR=\fPnr |
57e118a2 | 76 | Set the maximum allowed number of jobs (threads/processes) to support. |
d60e92d1 | 77 | .TP |
49da1240 JA |
78 | .BI \-\-server \fR=\fPargs |
79 | Start a backend server, with \fIargs\fP specifying what to listen to. See client/server section. | |
f57a9c59 | 80 | .TP |
49da1240 JA |
81 | .BI \-\-daemonize \fR=\fPpidfile |
82 | Background a fio server, writing the pid to the given pid file. | |
83 | .TP | |
84 | .BI \-\-client \fR=\fPhost | |
85 | Instead of running the jobs locally, send and run them on the given host. | |
f2a2ce0e HL |
86 | .TP |
87 | .BI \-\-idle\-prof \fR=\fPoption | |
88 | Report cpu idleness on a system or percpu basis (\fIoption\fP=system,percpu) or run unit work calibration only (\fIoption\fP=calibrate). | |
d60e92d1 AC |
89 | .SH "JOB FILE FORMAT" |
90 | Job files are in `ini' format. They consist of one or more | |
91 | job definitions, which begin with a job name in square brackets and | |
92 | extend to the next job name. The job name can be any ASCII string | |
93 | except `global', which has a special meaning. Following the job name is | |
94 | a sequence of zero or more parameters, one per line, that define the | |
95 | behavior of the job. Any line starting with a `;' or `#' character is | |
d1429b5c | 96 | considered a comment and ignored. |
d9956b64 AC |
97 | .P |
98 | If \fIjobfile\fR is specified as `-', the job file will be read from | |
99 | standard input. | |
d60e92d1 AC |
100 | .SS "Global Section" |
101 | The global section contains default parameters for jobs specified in the | |
102 | job file. A job is only affected by global sections residing above it, | |
103 | and there may be any number of global sections. Specific job definitions | |
104 | may override any parameter set in global sections. | |
105 | .SH "JOB PARAMETERS" | |
106 | .SS Types | |
107 | Some parameters may take arguments of a specific type. The types used are: | |
108 | .TP | |
109 | .I str | |
110 | String: a sequence of alphanumeric characters. | |
111 | .TP | |
112 | .I int | |
d60e92d1 | 113 | SI integer: a whole number, possibly containing a suffix denoting the base unit |
b09da8fa JA |
114 | of the value. Accepted suffixes are `k', 'M', 'G', 'T', and 'P', denoting |
115 | kilo (1024), mega (1024^2), giga (1024^3), tera (1024^4), and peta (1024^5) | |
116 | respectively. The suffix is not case sensitive. If prefixed with '0x', the | |
5982a925 MS |
117 | value is assumed to be base 16 (hexadecimal). A suffix may include a trailing 'b', |
118 | for instance 'kb' is identical to 'k'. You can specify a base 10 value | |
57fc29fa JA |
119 | by using 'KiB', 'MiB', 'GiB', etc. This is useful for disk drives where |
120 | values are often given in base 10 values. Specifying '30GiB' will get you | |
121 | 30*1000^3 bytes. | |
d60e92d1 AC |
122 | .TP |
123 | .I bool | |
124 | Boolean: a true or false value. `0' denotes false, `1' denotes true. | |
125 | .TP | |
126 | .I irange | |
127 | Integer range: a range of integers specified in the format | |
d1429b5c AC |
128 | \fIlower\fR:\fIupper\fR or \fIlower\fR\-\fIupper\fR. \fIlower\fR and |
129 | \fIupper\fR may contain a suffix as described above. If an option allows two | |
130 | sets of ranges, they are separated with a `,' or `/' character. For example: | |
131 | `8\-8k/8M\-4G'. | |
83349190 YH |
132 | .TP |
133 | .I float_list | |
134 | List of floating numbers: A list of floating numbers, separated by | |
cecbfd47 | 135 | a ':' character. |
d60e92d1 AC |
136 | .SS "Parameter List" |
137 | .TP | |
138 | .BI name \fR=\fPstr | |
d9956b64 | 139 | May be used to override the job name. On the command line, this parameter |
d60e92d1 AC |
140 | has the special purpose of signalling the start of a new job. |
141 | .TP | |
142 | .BI description \fR=\fPstr | |
143 | Human-readable description of the job. It is printed when the job is run, but | |
144 | otherwise has no special purpose. | |
145 | .TP | |
146 | .BI directory \fR=\fPstr | |
147 | Prefix filenames with this directory. Used to place files in a location other | |
148 | than `./'. | |
149 | .TP | |
150 | .BI filename \fR=\fPstr | |
151 | .B fio | |
152 | normally makes up a file name based on the job name, thread number, and file | |
d1429b5c | 153 | number. If you want to share files between threads in a job or several jobs, |
de890a1e SL |
154 | specify a \fIfilename\fR for each of them to override the default. |
155 | If the I/O engine is file-based, you can specify | |
d1429b5c AC |
156 | a number of files by separating the names with a `:' character. `\-' is a |
157 | reserved name, meaning stdin or stdout, depending on the read/write direction | |
158 | set. | |
d60e92d1 | 159 | .TP |
de98bd30 | 160 | .BI filename_format \fR=\fPstr |
ce594fbe | 161 | If sharing multiple files between jobs, it is usually necessary to have |
de98bd30 JA |
162 | fio generate the exact names that you want. By default, fio will name a file |
163 | based on the default file format specification of | |
164 | \fBjobname.jobnumber.filenumber\fP. With this option, that can be | |
165 | customized. Fio will recognize and replace the following keywords in this | |
166 | string: | |
167 | .RS | |
168 | .RS | |
169 | .TP | |
170 | .B $jobname | |
171 | The name of the worker thread or process. | |
172 | .TP | |
173 | .B $jobnum | |
174 | The incremental number of the worker thread or process. | |
175 | .TP | |
176 | .B $filenum | |
177 | The incremental number of the file for that worker thread or process. | |
178 | .RE | |
179 | .P | |
180 | To have dependent jobs share a set of files, this option can be set to | |
181 | have fio generate filenames that are shared between the two. For instance, | |
182 | if \fBtestfiles.$filenum\fR is specified, file number 4 for any job will | |
183 | be named \fBtestfiles.4\fR. The default of \fB$jobname.$jobnum.$filenum\fR | |
184 | will be used if no other format specifier is given. | |
185 | .RE | |
186 | .P | |
187 | .TP | |
3ce9dcaf JA |
188 | .BI lockfile \fR=\fPstr |
189 | Fio defaults to not locking any files before it does IO to them. If a file or | |
190 | file descriptor is shared, fio can serialize IO to that file to make the end | |
191 | result consistent. This is usual for emulating real workloads that share files. | |
192 | The lock modes are: | |
193 | .RS | |
194 | .RS | |
195 | .TP | |
196 | .B none | |
197 | No locking. This is the default. | |
198 | .TP | |
199 | .B exclusive | |
200 | Only one thread or process may do IO at the time, excluding all others. | |
201 | .TP | |
202 | .B readwrite | |
203 | Read-write locking on the file. Many readers may access the file at the same | |
204 | time, but writes get exclusive access. | |
205 | .RE | |
ce594fbe | 206 | .RE |
3ce9dcaf | 207 | .P |
d60e92d1 AC |
208 | .BI opendir \fR=\fPstr |
209 | Recursively open any files below directory \fIstr\fR. | |
210 | .TP | |
211 | .BI readwrite \fR=\fPstr "\fR,\fP rw" \fR=\fPstr | |
212 | Type of I/O pattern. Accepted values are: | |
213 | .RS | |
214 | .RS | |
215 | .TP | |
216 | .B read | |
d1429b5c | 217 | Sequential reads. |
d60e92d1 AC |
218 | .TP |
219 | .B write | |
d1429b5c | 220 | Sequential writes. |
d60e92d1 | 221 | .TP |
fa769d44 SW |
222 | .B trim |
223 | Sequential trim (Linux block devices only). | |
224 | .TP | |
d60e92d1 | 225 | .B randread |
d1429b5c | 226 | Random reads. |
d60e92d1 AC |
227 | .TP |
228 | .B randwrite | |
d1429b5c | 229 | Random writes. |
d60e92d1 | 230 | .TP |
fa769d44 SW |
231 | .B randtrim |
232 | Random trim (Linux block devices only). | |
233 | .TP | |
10b023db | 234 | .B rw, readwrite |
d1429b5c | 235 | Mixed sequential reads and writes. |
d60e92d1 AC |
236 | .TP |
237 | .B randrw | |
d1429b5c | 238 | Mixed random reads and writes. |
d60e92d1 AC |
239 | .RE |
240 | .P | |
38dad62d JA |
241 | For mixed I/O, the default split is 50/50. For certain types of io the result |
242 | may still be skewed a bit, since the speed may be different. It is possible to | |
3b7fa9ec | 243 | specify a number of IO's to do before getting a new offset, this is done by |
38dad62d JA |
244 | appending a `:\fI<nr>\fR to the end of the string given. For a random read, it |
245 | would look like \fBrw=randread:8\fR for passing in an offset modifier with a | |
059b0802 JA |
246 | value of 8. If the postfix is used with a sequential IO pattern, then the value |
247 | specified will be added to the generated offset for each IO. For instance, | |
248 | using \fBrw=write:4k\fR will skip 4k for every write. It turns sequential IO | |
249 | into sequential IO with holes. See the \fBrw_sequencer\fR option. | |
d60e92d1 AC |
250 | .RE |
251 | .TP | |
38dad62d JA |
252 | .BI rw_sequencer \fR=\fPstr |
253 | If an offset modifier is given by appending a number to the \fBrw=<str>\fR line, | |
254 | then this option controls how that number modifies the IO offset being | |
255 | generated. Accepted values are: | |
256 | .RS | |
257 | .RS | |
258 | .TP | |
259 | .B sequential | |
260 | Generate sequential offset | |
261 | .TP | |
262 | .B identical | |
263 | Generate the same offset | |
264 | .RE | |
265 | .P | |
266 | \fBsequential\fR is only useful for random IO, where fio would normally | |
267 | generate a new random offset for every IO. If you append eg 8 to randread, you | |
268 | would get a new random offset for every 8 IO's. The result would be a seek for | |
269 | only every 8 IO's, instead of for every IO. Use \fBrw=randread:8\fR to specify | |
270 | that. As sequential IO is already sequential, setting \fBsequential\fR for that | |
271 | would not result in any differences. \fBidentical\fR behaves in a similar | |
272 | fashion, except it sends the same offset 8 number of times before generating a | |
273 | new offset. | |
274 | .RE | |
275 | .P | |
276 | .TP | |
90fef2d1 JA |
277 | .BI kb_base \fR=\fPint |
278 | The base unit for a kilobyte. The defacto base is 2^10, 1024. Storage | |
279 | manufacturers like to use 10^3 or 1000 as a base ten unit instead, for obvious | |
5c9323fb | 280 | reasons. Allowed values are 1024 or 1000, with 1024 being the default. |
90fef2d1 | 281 | .TP |
771e58be JA |
282 | .BI unified_rw_reporting \fR=\fPbool |
283 | Fio normally reports statistics on a per data direction basis, meaning that | |
284 | read, write, and trim are accounted and reported separately. If this option is | |
285 | set, the fio will sum the results and report them as "mixed" instead. | |
286 | .TP | |
d60e92d1 AC |
287 | .BI randrepeat \fR=\fPbool |
288 | Seed the random number generator in a predictable way so results are repeatable | |
d1429b5c | 289 | across runs. Default: true. |
d60e92d1 | 290 | .TP |
04778baf JA |
291 | .BI randseed \fR=\fPint |
292 | Seed the random number generators based on this seed value, to be able to | |
293 | control what sequence of output is being generated. If not set, the random | |
294 | sequence depends on the \fBrandrepeat\fR setting. | |
295 | .TP | |
2615cc4b JA |
296 | .BI use_os_rand \fR=\fPbool |
297 | Fio can either use the random generator supplied by the OS to generator random | |
298 | offsets, or it can use it's own internal generator (based on Tausworthe). | |
299 | Default is to use the internal generator, which is often of better quality and | |
300 | faster. Default: false. | |
301 | .TP | |
a596f047 EG |
302 | .BI fallocate \fR=\fPstr |
303 | Whether pre-allocation is performed when laying down files. Accepted values | |
304 | are: | |
305 | .RS | |
306 | .RS | |
307 | .TP | |
308 | .B none | |
309 | Do not pre-allocate space. | |
310 | .TP | |
311 | .B posix | |
ccc2b328 | 312 | Pre-allocate via \fBposix_fallocate\fR\|(3). |
a596f047 EG |
313 | .TP |
314 | .B keep | |
ccc2b328 | 315 | Pre-allocate via \fBfallocate\fR\|(2) with FALLOC_FL_KEEP_SIZE set. |
a596f047 EG |
316 | .TP |
317 | .B 0 | |
318 | Backward-compatible alias for 'none'. | |
319 | .TP | |
320 | .B 1 | |
321 | Backward-compatible alias for 'posix'. | |
322 | .RE | |
323 | .P | |
324 | May not be available on all supported platforms. 'keep' is only | |
325 | available on Linux. If using ZFS on Solaris this must be set to 'none' | |
326 | because ZFS doesn't support it. Default: 'posix'. | |
327 | .RE | |
7bc8c2cf | 328 | .TP |
d60e92d1 | 329 | .BI fadvise_hint \fR=\fPbool |
ccc2b328 | 330 | Use of \fBposix_fadvise\fR\|(2) to advise the kernel what I/O patterns |
d1429b5c | 331 | are likely to be issued. Default: true. |
d60e92d1 | 332 | .TP |
f7fa2653 | 333 | .BI size \fR=\fPint |
d60e92d1 | 334 | Total size of I/O for this job. \fBfio\fR will run until this many bytes have |
ca45881f | 335 | been transferred, unless limited by other options (\fBruntime\fR, for instance). |
d7c8be03 | 336 | Unless \fBnrfiles\fR and \fBfilesize\fR options are given, this amount will be |
d6667268 | 337 | divided between the available files for the job. If not set, fio will use the |
cecbfd47 | 338 | full size of the given files or devices. If the files do not exist, size |
7bb59102 JA |
339 | must be given. It is also possible to give size as a percentage between 1 and |
340 | 100. If size=20% is given, fio will use 20% of the full size of the given files | |
341 | or devices. | |
d60e92d1 | 342 | .TP |
74586c1e | 343 | .BI fill_device \fR=\fPbool "\fR,\fB fill_fs" \fR=\fPbool |
3ce9dcaf JA |
344 | Sets size to something really large and waits for ENOSPC (no space left on |
345 | device) as the terminating condition. Only makes sense with sequential write. | |
346 | For a read workload, the mount point will be filled first then IO started on | |
4f12432e JA |
347 | the result. This option doesn't make sense if operating on a raw device node, |
348 | since the size of that is already known by the file system. Additionally, | |
349 | writing beyond end-of-device will not return ENOSPC there. | |
3ce9dcaf | 350 | .TP |
d60e92d1 AC |
351 | .BI filesize \fR=\fPirange |
352 | Individual file sizes. May be a range, in which case \fBfio\fR will select sizes | |
d1429b5c AC |
353 | for files at random within the given range, limited to \fBsize\fR in total (if |
354 | that is given). If \fBfilesize\fR is not specified, each created file is the | |
355 | same size. | |
d60e92d1 | 356 | .TP |
f7fa2653 | 357 | .BI blocksize \fR=\fPint[,int] "\fR,\fB bs" \fR=\fPint[,int] |
d9472271 JA |
358 | Block size for I/O units. Default: 4k. Values for reads, writes, and trims |
359 | can be specified separately in the format \fIread\fR,\fIwrite\fR,\fItrim\fR | |
360 | either of which may be empty to leave that value at its default. If a trailing | |
361 | comma isn't given, the remainder will inherit the last value set. | |
d60e92d1 | 362 | .TP |
9183788d | 363 | .BI blocksize_range \fR=\fPirange[,irange] "\fR,\fB bsrange" \fR=\fPirange[,irange] |
d1429b5c AC |
364 | Specify a range of I/O block sizes. The issued I/O unit will always be a |
365 | multiple of the minimum size, unless \fBblocksize_unaligned\fR is set. Applies | |
9183788d | 366 | to both reads and writes if only one range is given, but can be specified |
de8f6de9 | 367 | separately with a comma separating the values. Example: bsrange=1k-4k,2k-8k. |
9183788d JA |
368 | Also (see \fBblocksize\fR). |
369 | .TP | |
370 | .BI bssplit \fR=\fPstr | |
371 | This option allows even finer grained control of the block sizes issued, | |
372 | not just even splits between them. With this option, you can weight various | |
373 | block sizes for exact control of the issued IO for a job that has mixed | |
374 | block sizes. The format of the option is bssplit=blocksize/percentage, | |
5982a925 | 375 | optionally adding as many definitions as needed separated by a colon. |
9183788d | 376 | Example: bssplit=4k/10:64k/50:32k/40 would issue 50% 64k blocks, 10% 4k |
c83cdd3e JA |
377 | blocks and 40% 32k blocks. \fBbssplit\fR also supports giving separate |
378 | splits to reads and writes. The format is identical to what the | |
379 | \fBbs\fR option accepts, the read and write parts are separated with a | |
380 | comma. | |
d60e92d1 AC |
381 | .TP |
382 | .B blocksize_unaligned\fR,\fP bs_unaligned | |
d1429b5c AC |
383 | If set, any size in \fBblocksize_range\fR may be used. This typically won't |
384 | work with direct I/O, as that normally requires sector alignment. | |
d60e92d1 | 385 | .TP |
2b7a01d0 | 386 | .BI blockalign \fR=\fPint[,int] "\fR,\fB ba" \fR=\fPint[,int] |
639ce0f3 MS |
387 | At what boundary to align random IO offsets. Defaults to the same as 'blocksize' |
388 | the minimum blocksize given. Minimum alignment is typically 512b | |
2b7a01d0 JA |
389 | for using direct IO, though it usually depends on the hardware block size. |
390 | This option is mutually exclusive with using a random map for files, so it | |
391 | will turn off that option. | |
43602667 | 392 | .TP |
6aca9b3d JA |
393 | .BI bs_is_seq_rand \fR=\fPbool |
394 | If this option is set, fio will use the normal read,write blocksize settings as | |
395 | sequential,random instead. Any random read or write will use the WRITE | |
396 | blocksize settings, and any sequential read or write will use the READ | |
397 | blocksize setting. | |
398 | .TP | |
d60e92d1 AC |
399 | .B zero_buffers |
400 | Initialise buffers with all zeros. Default: fill buffers with random data. | |
401 | .TP | |
901bb994 JA |
402 | .B refill_buffers |
403 | If this option is given, fio will refill the IO buffers on every submit. The | |
404 | default is to only fill it at init time and reuse that data. Only makes sense | |
405 | if zero_buffers isn't specified, naturally. If data verification is enabled, | |
406 | refill_buffers is also automatically enabled. | |
407 | .TP | |
fd68418e JA |
408 | .BI scramble_buffers \fR=\fPbool |
409 | If \fBrefill_buffers\fR is too costly and the target is using data | |
410 | deduplication, then setting this option will slightly modify the IO buffer | |
411 | contents to defeat normal de-dupe attempts. This is not enough to defeat | |
412 | more clever block compression attempts, but it will stop naive dedupe | |
413 | of blocks. Default: true. | |
414 | .TP | |
c5751c62 JA |
415 | .BI buffer_compress_percentage \fR=\fPint |
416 | If this is set, then fio will attempt to provide IO buffer content (on WRITEs) | |
417 | that compress to the specified level. Fio does this by providing a mix of | |
418 | random data and zeroes. Note that this is per block size unit, for file/disk | |
419 | wide compression level that matches this setting, you'll also want to set | |
420 | \fBrefill_buffers\fR. | |
421 | .TP | |
422 | .BI buffer_compress_chunk \fR=\fPint | |
423 | See \fBbuffer_compress_percentage\fR. This setting allows fio to manage how | |
424 | big the ranges of random data and zeroed data is. Without this set, fio will | |
425 | provide \fBbuffer_compress_percentage\fR of blocksize random data, followed by | |
426 | the remaining zeroed. With this set to some chunk size smaller than the block | |
427 | size, fio can alternate random and zeroed data throughout the IO buffer. | |
428 | .TP | |
ce35b1ec JA |
429 | .BI buffer_pattern \fR=\fPstr |
430 | If set, fio will fill the io buffers with this pattern. If not set, the contents | |
431 | of io buffers is defined by the other options related to buffer contents. The | |
432 | setting can be any pattern of bytes, and can be prefixed with 0x for hex | |
433 | values. | |
434 | .TP | |
d60e92d1 AC |
435 | .BI nrfiles \fR=\fPint |
436 | Number of files to use for this job. Default: 1. | |
437 | .TP | |
438 | .BI openfiles \fR=\fPint | |
439 | Number of files to keep open at the same time. Default: \fBnrfiles\fR. | |
440 | .TP | |
441 | .BI file_service_type \fR=\fPstr | |
442 | Defines how files to service are selected. The following types are defined: | |
443 | .RS | |
444 | .RS | |
445 | .TP | |
446 | .B random | |
5c9323fb | 447 | Choose a file at random. |
d60e92d1 AC |
448 | .TP |
449 | .B roundrobin | |
450 | Round robin over open files (default). | |
5c9323fb | 451 | .TP |
6b7f6851 JA |
452 | .B sequential |
453 | Do each file in the set sequentially. | |
d60e92d1 AC |
454 | .RE |
455 | .P | |
456 | The number of I/Os to issue before switching a new file can be specified by | |
457 | appending `:\fIint\fR' to the service type. | |
458 | .RE | |
459 | .TP | |
460 | .BI ioengine \fR=\fPstr | |
461 | Defines how the job issues I/O. The following types are defined: | |
462 | .RS | |
463 | .RS | |
464 | .TP | |
465 | .B sync | |
ccc2b328 | 466 | Basic \fBread\fR\|(2) or \fBwrite\fR\|(2) I/O. \fBfseek\fR\|(2) is used to |
d60e92d1 AC |
467 | position the I/O location. |
468 | .TP | |
a31041ea | 469 | .B psync |
ccc2b328 | 470 | Basic \fBpread\fR\|(2) or \fBpwrite\fR\|(2) I/O. |
a31041ea | 471 | .TP |
9183788d | 472 | .B vsync |
ccc2b328 | 473 | Basic \fBreadv\fR\|(2) or \fBwritev\fR\|(2) I/O. Will emulate queuing by |
cecbfd47 | 474 | coalescing adjacent IOs into a single submission. |
9183788d | 475 | .TP |
a46c5e01 | 476 | .B pvsync |
ccc2b328 | 477 | Basic \fBpreadv\fR\|(2) or \fBpwritev\fR\|(2) I/O. |
a46c5e01 | 478 | .TP |
d60e92d1 | 479 | .B libaio |
de890a1e | 480 | Linux native asynchronous I/O. This ioengine defines engine specific options. |
d60e92d1 AC |
481 | .TP |
482 | .B posixaio | |
ccc2b328 | 483 | POSIX asynchronous I/O using \fBaio_read\fR\|(3) and \fBaio_write\fR\|(3). |
03e20d68 BC |
484 | .TP |
485 | .B solarisaio | |
486 | Solaris native asynchronous I/O. | |
487 | .TP | |
488 | .B windowsaio | |
489 | Windows native asynchronous I/O. | |
d60e92d1 AC |
490 | .TP |
491 | .B mmap | |
ccc2b328 SW |
492 | File is memory mapped with \fBmmap\fR\|(2) and data copied using |
493 | \fBmemcpy\fR\|(3). | |
d60e92d1 AC |
494 | .TP |
495 | .B splice | |
ccc2b328 | 496 | \fBsplice\fR\|(2) is used to transfer the data and \fBvmsplice\fR\|(2) to |
d1429b5c | 497 | transfer data from user-space to the kernel. |
d60e92d1 AC |
498 | .TP |
499 | .B syslet-rw | |
500 | Use the syslet system calls to make regular read/write asynchronous. | |
501 | .TP | |
502 | .B sg | |
503 | SCSI generic sg v3 I/O. May be either synchronous using the SG_IO ioctl, or if | |
ccc2b328 SW |
504 | the target is an sg character device, we use \fBread\fR\|(2) and |
505 | \fBwrite\fR\|(2) for asynchronous I/O. | |
d60e92d1 AC |
506 | .TP |
507 | .B null | |
508 | Doesn't transfer any data, just pretends to. Mainly used to exercise \fBfio\fR | |
509 | itself and for debugging and testing purposes. | |
510 | .TP | |
511 | .B net | |
de890a1e SL |
512 | Transfer over the network. The protocol to be used can be defined with the |
513 | \fBprotocol\fR parameter. Depending on the protocol, \fBfilename\fR, | |
514 | \fBhostname\fR, \fBport\fR, or \fBlisten\fR must be specified. | |
515 | This ioengine defines engine specific options. | |
d60e92d1 AC |
516 | .TP |
517 | .B netsplice | |
ccc2b328 | 518 | Like \fBnet\fR, but uses \fBsplice\fR\|(2) and \fBvmsplice\fR\|(2) to map data |
de890a1e | 519 | and send/receive. This ioengine defines engine specific options. |
d60e92d1 | 520 | .TP |
53aec0a4 | 521 | .B cpuio |
d60e92d1 AC |
522 | Doesn't transfer any data, but burns CPU cycles according to \fBcpuload\fR and |
523 | \fBcpucycles\fR parameters. | |
524 | .TP | |
525 | .B guasi | |
526 | The GUASI I/O engine is the Generic Userspace Asynchronous Syscall Interface | |
cecbfd47 | 527 | approach to asynchronous I/O. |
d1429b5c AC |
528 | .br |
529 | See <http://www.xmailserver.org/guasi\-lib.html>. | |
d60e92d1 | 530 | .TP |
21b8aee8 | 531 | .B rdma |
85286c5c BVA |
532 | The RDMA I/O engine supports both RDMA memory semantics (RDMA_WRITE/RDMA_READ) |
533 | and channel semantics (Send/Recv) for the InfiniBand, RoCE and iWARP protocols. | |
21b8aee8 | 534 | .TP |
d60e92d1 AC |
535 | .B external |
536 | Loads an external I/O engine object file. Append the engine filename as | |
537 | `:\fIenginepath\fR'. | |
d54fce84 DM |
538 | .TP |
539 | .B falloc | |
cecbfd47 | 540 | IO engine that does regular linux native fallocate call to simulate data |
d54fce84 DM |
541 | transfer as fio ioengine |
542 | .br | |
543 | DDIR_READ does fallocate(,mode = FALLOC_FL_KEEP_SIZE,) | |
544 | .br | |
0981fd71 | 545 | DIR_WRITE does fallocate(,mode = 0) |
d54fce84 DM |
546 | .br |
547 | DDIR_TRIM does fallocate(,mode = FALLOC_FL_KEEP_SIZE|FALLOC_FL_PUNCH_HOLE) | |
548 | .TP | |
549 | .B e4defrag | |
550 | IO engine that does regular EXT4_IOC_MOVE_EXT ioctls to simulate defragment activity | |
551 | request to DDIR_WRITE event | |
d60e92d1 | 552 | .RE |
595e1734 | 553 | .P |
d60e92d1 AC |
554 | .RE |
555 | .TP | |
556 | .BI iodepth \fR=\fPint | |
8489dae4 SK |
557 | Number of I/O units to keep in flight against the file. Note that increasing |
558 | iodepth beyond 1 will not affect synchronous ioengines (except for small | |
ee72ca09 JA |
559 | degress when verify_async is in use). Even async engines my impose OS |
560 | restrictions causing the desired depth not to be achieved. This may happen on | |
561 | Linux when using libaio and not setting \fBdirect\fR=1, since buffered IO is | |
562 | not async on that OS. Keep an eye on the IO depth distribution in the | |
563 | fio output to verify that the achieved depth is as expected. Default: 1. | |
d60e92d1 AC |
564 | .TP |
565 | .BI iodepth_batch \fR=\fPint | |
566 | Number of I/Os to submit at once. Default: \fBiodepth\fR. | |
567 | .TP | |
3ce9dcaf JA |
568 | .BI iodepth_batch_complete \fR=\fPint |
569 | This defines how many pieces of IO to retrieve at once. It defaults to 1 which | |
570 | means that we'll ask for a minimum of 1 IO in the retrieval process from the | |
571 | kernel. The IO retrieval will go on until we hit the limit set by | |
572 | \fBiodepth_low\fR. If this variable is set to 0, then fio will always check for | |
573 | completed events before queuing more IO. This helps reduce IO latency, at the | |
574 | cost of more retrieval system calls. | |
575 | .TP | |
d60e92d1 AC |
576 | .BI iodepth_low \fR=\fPint |
577 | Low watermark indicating when to start filling the queue again. Default: | |
578 | \fBiodepth\fR. | |
579 | .TP | |
580 | .BI direct \fR=\fPbool | |
581 | If true, use non-buffered I/O (usually O_DIRECT). Default: false. | |
582 | .TP | |
d01612f3 CM |
583 | .BI atomic \fR=\fPbool |
584 | If value is true, attempt to use atomic direct IO. Atomic writes are guaranteed | |
585 | to be stable once acknowledged by the operating system. Only Linux supports | |
586 | O_ATOMIC right now. | |
587 | .TP | |
d60e92d1 AC |
588 | .BI buffered \fR=\fPbool |
589 | If true, use buffered I/O. This is the opposite of the \fBdirect\fR parameter. | |
590 | Default: true. | |
591 | .TP | |
f7fa2653 | 592 | .BI offset \fR=\fPint |
d60e92d1 AC |
593 | Offset in the file to start I/O. Data before the offset will not be touched. |
594 | .TP | |
591e9e06 JA |
595 | .BI offset_increment \fR=\fPint |
596 | If this is provided, then the real offset becomes the | |
597 | offset + offset_increment * thread_number, where the thread number is a counter | |
598 | that starts at 0 and is incremented for each job. This option is useful if | |
599 | there are several jobs which are intended to operate on a file in parallel in | |
600 | disjoint segments, with even spacing between the starting points. | |
601 | .TP | |
ddf24e42 JA |
602 | .BI number_ios \fR=\fPint |
603 | Fio will normally perform IOs until it has exhausted the size of the region | |
604 | set by \fBsize\fR, or if it exhaust the allocated time (or hits an error | |
605 | condition). With this setting, the range/size can be set independently of | |
606 | the number of IOs to perform. When fio reaches this number, it will exit | |
607 | normally and report status. | |
608 | .TP | |
d60e92d1 | 609 | .BI fsync \fR=\fPint |
d1429b5c AC |
610 | How many I/Os to perform before issuing an \fBfsync\fR\|(2) of dirty data. If |
611 | 0, don't sync. Default: 0. | |
d60e92d1 | 612 | .TP |
5f9099ea JA |
613 | .BI fdatasync \fR=\fPint |
614 | Like \fBfsync\fR, but uses \fBfdatasync\fR\|(2) instead to only sync the | |
615 | data parts of the file. Default: 0. | |
616 | .TP | |
fa769d44 SW |
617 | .BI write_barrier \fR=\fPint |
618 | Make every Nth write a barrier write. | |
619 | .TP | |
e76b1da4 | 620 | .BI sync_file_range \fR=\fPstr:int |
ccc2b328 SW |
621 | Use \fBsync_file_range\fR\|(2) for every \fRval\fP number of write operations. Fio will |
622 | track range of writes that have happened since the last \fBsync_file_range\fR\|(2) call. | |
e76b1da4 JA |
623 | \fRstr\fP can currently be one or more of: |
624 | .RS | |
625 | .TP | |
626 | .B wait_before | |
627 | SYNC_FILE_RANGE_WAIT_BEFORE | |
628 | .TP | |
629 | .B write | |
630 | SYNC_FILE_RANGE_WRITE | |
631 | .TP | |
632 | .B wait_after | |
633 | SYNC_FILE_RANGE_WRITE | |
634 | .TP | |
635 | .RE | |
636 | .P | |
637 | So if you do sync_file_range=wait_before,write:8, fio would use | |
638 | \fBSYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE\fP for every 8 writes. | |
ccc2b328 | 639 | Also see the \fBsync_file_range\fR\|(2) man page. This option is Linux specific. |
e76b1da4 | 640 | .TP |
d60e92d1 | 641 | .BI overwrite \fR=\fPbool |
d1429b5c | 642 | If writing, setup the file first and do overwrites. Default: false. |
d60e92d1 AC |
643 | .TP |
644 | .BI end_fsync \fR=\fPbool | |
dbd11ead | 645 | Sync file contents when a write stage has completed. Default: false. |
d60e92d1 AC |
646 | .TP |
647 | .BI fsync_on_close \fR=\fPbool | |
648 | If true, sync file contents on close. This differs from \fBend_fsync\fR in that | |
d1429b5c | 649 | it will happen on every close, not just at the end of the job. Default: false. |
d60e92d1 | 650 | .TP |
d60e92d1 AC |
651 | .BI rwmixread \fR=\fPint |
652 | Percentage of a mixed workload that should be reads. Default: 50. | |
653 | .TP | |
654 | .BI rwmixwrite \fR=\fPint | |
d1429b5c | 655 | Percentage of a mixed workload that should be writes. If \fBrwmixread\fR and |
c35dd7a6 JA |
656 | \fBrwmixwrite\fR are given and do not sum to 100%, the latter of the two |
657 | overrides the first. This may interfere with a given rate setting, if fio is | |
658 | asked to limit reads or writes to a certain rate. If that is the case, then | |
659 | the distribution may be skewed. Default: 50. | |
d60e92d1 | 660 | .TP |
92d42d69 JA |
661 | .BI random_distribution \fR=\fPstr:float |
662 | By default, fio will use a completely uniform random distribution when asked | |
663 | to perform random IO. Sometimes it is useful to skew the distribution in | |
664 | specific ways, ensuring that some parts of the data is more hot than others. | |
665 | Fio includes the following distribution models: | |
666 | .RS | |
667 | .TP | |
668 | .B random | |
669 | Uniform random distribution | |
670 | .TP | |
671 | .B zipf | |
672 | Zipf distribution | |
673 | .TP | |
674 | .B pareto | |
675 | Pareto distribution | |
676 | .TP | |
677 | .RE | |
678 | .P | |
679 | When using a zipf or pareto distribution, an input value is also needed to | |
680 | define the access pattern. For zipf, this is the zipf theta. For pareto, | |
681 | it's the pareto power. Fio includes a test program, genzipf, that can be | |
682 | used visualize what the given input values will yield in terms of hit rates. | |
683 | If you wanted to use zipf with a theta of 1.2, you would use | |
684 | random_distribution=zipf:1.2 as the option. If a non-uniform model is used, | |
685 | fio will disable use of the random map. | |
686 | .TP | |
211c9b89 JA |
687 | .BI percentage_random \fR=\fPint |
688 | For a random workload, set how big a percentage should be random. This defaults | |
689 | to 100%, in which case the workload is fully random. It can be set from | |
690 | anywhere from 0 to 100. Setting it to 0 would make the workload fully | |
d9472271 JA |
691 | sequential. It is possible to set different values for reads, writes, and |
692 | trim. To do so, simply use a comma separated list. See \fBblocksize\fR. | |
211c9b89 | 693 | .TP |
d60e92d1 AC |
694 | .B norandommap |
695 | Normally \fBfio\fR will cover every block of the file when doing random I/O. If | |
696 | this parameter is given, a new offset will be chosen without looking at past | |
697 | I/O history. This parameter is mutually exclusive with \fBverify\fR. | |
698 | .TP | |
744492c9 | 699 | .BI softrandommap \fR=\fPbool |
3ce9dcaf JA |
700 | See \fBnorandommap\fR. If fio runs with the random block map enabled and it |
701 | fails to allocate the map, if this option is set it will continue without a | |
702 | random block map. As coverage will not be as complete as with random maps, this | |
703 | option is disabled by default. | |
704 | .TP | |
e8b1961d JA |
705 | .BI random_generator \fR=\fPstr |
706 | Fio supports the following engines for generating IO offsets for random IO: | |
707 | .RS | |
708 | .TP | |
709 | .B tausworthe | |
710 | Strong 2^88 cycle random number generator | |
711 | .TP | |
712 | .B lfsr | |
713 | Linear feedback shift register generator | |
714 | .TP | |
715 | .RE | |
716 | .P | |
717 | Tausworthe is a strong random number generator, but it requires tracking on the | |
718 | side if we want to ensure that blocks are only read or written once. LFSR | |
719 | guarantees that we never generate the same offset twice, and it's also less | |
720 | computationally expensive. It's not a true random generator, however, though | |
721 | for IO purposes it's typically good enough. LFSR only works with single block | |
722 | sizes, not with workloads that use multiple block sizes. If used with such a | |
723 | workload, fio may read or write some blocks multiple times. | |
724 | .TP | |
d60e92d1 | 725 | .BI nice \fR=\fPint |
ccc2b328 | 726 | Run job with given nice value. See \fBnice\fR\|(2). |
d60e92d1 AC |
727 | .TP |
728 | .BI prio \fR=\fPint | |
729 | Set I/O priority value of this job between 0 (highest) and 7 (lowest). See | |
ccc2b328 | 730 | \fBionice\fR\|(1). |
d60e92d1 AC |
731 | .TP |
732 | .BI prioclass \fR=\fPint | |
ccc2b328 | 733 | Set I/O priority class. See \fBionice\fR\|(1). |
d60e92d1 AC |
734 | .TP |
735 | .BI thinktime \fR=\fPint | |
736 | Stall job for given number of microseconds between issuing I/Os. | |
737 | .TP | |
738 | .BI thinktime_spin \fR=\fPint | |
739 | Pretend to spend CPU time for given number of microseconds, sleeping the rest | |
740 | of the time specified by \fBthinktime\fR. Only valid if \fBthinktime\fR is set. | |
741 | .TP | |
742 | .BI thinktime_blocks \fR=\fPint | |
4d01ece6 JA |
743 | Only valid if thinktime is set - control how many blocks to issue, before |
744 | waiting \fBthinktime\fR microseconds. If not set, defaults to 1 which will | |
745 | make fio wait \fBthinktime\fR microseconds after every block. This | |
746 | effectively makes any queue depth setting redundant, since no more than 1 IO | |
747 | will be queued before we have to complete it and do our thinktime. In other | |
748 | words, this setting effectively caps the queue depth if the latter is larger. | |
d60e92d1 AC |
749 | Default: 1. |
750 | .TP | |
751 | .BI rate \fR=\fPint | |
c35dd7a6 JA |
752 | Cap bandwidth used by this job. The number is in bytes/sec, the normal postfix |
753 | rules apply. You can use \fBrate\fR=500k to limit reads and writes to 500k each, | |
754 | or you can specify read and writes separately. Using \fBrate\fR=1m,500k would | |
755 | limit reads to 1MB/sec and writes to 500KB/sec. Capping only reads or writes | |
756 | can be done with \fBrate\fR=,500k or \fBrate\fR=500k,. The former will only | |
757 | limit writes (to 500KB/sec), the latter will only limit reads. | |
d60e92d1 AC |
758 | .TP |
759 | .BI ratemin \fR=\fPint | |
760 | Tell \fBfio\fR to do whatever it can to maintain at least the given bandwidth. | |
c35dd7a6 JA |
761 | Failing to meet this requirement will cause the job to exit. The same format |
762 | as \fBrate\fR is used for read vs write separation. | |
d60e92d1 AC |
763 | .TP |
764 | .BI rate_iops \fR=\fPint | |
c35dd7a6 JA |
765 | Cap the bandwidth to this number of IOPS. Basically the same as rate, just |
766 | specified independently of bandwidth. The same format as \fBrate\fR is used for | |
de8f6de9 | 767 | read vs write separation. If \fBblocksize\fR is a range, the smallest block |
c35dd7a6 | 768 | size is used as the metric. |
d60e92d1 AC |
769 | .TP |
770 | .BI rate_iops_min \fR=\fPint | |
c35dd7a6 | 771 | If this rate of I/O is not met, the job will exit. The same format as \fBrate\fR |
de8f6de9 | 772 | is used for read vs write separation. |
d60e92d1 AC |
773 | .TP |
774 | .BI ratecycle \fR=\fPint | |
775 | Average bandwidth for \fBrate\fR and \fBratemin\fR over this number of | |
776 | milliseconds. Default: 1000ms. | |
777 | .TP | |
3e260a46 JA |
778 | .BI latency_target \fR=\fPint |
779 | If set, fio will attempt to find the max performance point that the given | |
780 | workload will run at while maintaining a latency below this target. The | |
781 | values is given in microseconds. See \fBlatency_window\fR and | |
782 | \fBlatency_percentile\fR. | |
783 | .TP | |
784 | .BI latency_window \fR=\fPint | |
785 | Used with \fBlatency_target\fR to specify the sample window that the job | |
786 | is run at varying queue depths to test the performance. The value is given | |
787 | in microseconds. | |
788 | .TP | |
789 | .BI latency_percentile \fR=\fPfloat | |
790 | The percentage of IOs that must fall within the criteria specified by | |
791 | \fBlatency_target\fR and \fBlatency_window\fR. If not set, this defaults | |
792 | to 100.0, meaning that all IOs must be equal or below to the value set | |
793 | by \fBlatency_target\fR. | |
794 | .TP | |
15501535 JA |
795 | .BI max_latency \fR=\fPint |
796 | If set, fio will exit the job if it exceeds this maximum latency. It will exit | |
797 | with an ETIME error. | |
798 | .TP | |
d60e92d1 AC |
799 | .BI cpumask \fR=\fPint |
800 | Set CPU affinity for this job. \fIint\fR is a bitmask of allowed CPUs the job | |
801 | may run on. See \fBsched_setaffinity\fR\|(2). | |
802 | .TP | |
803 | .BI cpus_allowed \fR=\fPstr | |
804 | Same as \fBcpumask\fR, but allows a comma-delimited list of CPU numbers. | |
805 | .TP | |
d0b937ed | 806 | .BI numa_cpu_nodes \fR=\fPstr |
cecbfd47 | 807 | Set this job running on specified NUMA nodes' CPUs. The arguments allow |
d0b937ed YR |
808 | comma delimited list of cpu numbers, A-B ranges, or 'all'. |
809 | .TP | |
810 | .BI numa_mem_policy \fR=\fPstr | |
811 | Set this job's memory policy and corresponding NUMA nodes. Format of | |
cecbfd47 | 812 | the arguments: |
d0b937ed YR |
813 | .RS |
814 | .TP | |
815 | .B <mode>[:<nodelist>] | |
816 | .TP | |
817 | .B mode | |
818 | is one of the following memory policy: | |
819 | .TP | |
820 | .B default, prefer, bind, interleave, local | |
821 | .TP | |
822 | .RE | |
823 | For \fBdefault\fR and \fBlocal\fR memory policy, no \fBnodelist\fR is | |
824 | needed to be specified. For \fBprefer\fR, only one node is | |
825 | allowed. For \fBbind\fR and \fBinterleave\fR, \fBnodelist\fR allows | |
826 | comma delimited list of numbers, A-B ranges, or 'all'. | |
827 | .TP | |
d60e92d1 AC |
828 | .BI startdelay \fR=\fPint |
829 | Delay start of job for the specified number of seconds. | |
830 | .TP | |
831 | .BI runtime \fR=\fPint | |
832 | Terminate processing after the specified number of seconds. | |
833 | .TP | |
834 | .B time_based | |
835 | If given, run for the specified \fBruntime\fR duration even if the files are | |
836 | completely read or written. The same workload will be repeated as many times | |
837 | as \fBruntime\fR allows. | |
838 | .TP | |
901bb994 JA |
839 | .BI ramp_time \fR=\fPint |
840 | If set, fio will run the specified workload for this amount of time before | |
841 | logging any performance numbers. Useful for letting performance settle before | |
842 | logging results, thus minimizing the runtime required for stable results. Note | |
c35dd7a6 JA |
843 | that the \fBramp_time\fR is considered lead in time for a job, thus it will |
844 | increase the total runtime if a special timeout or runtime is specified. | |
901bb994 | 845 | .TP |
d60e92d1 AC |
846 | .BI invalidate \fR=\fPbool |
847 | Invalidate buffer-cache for the file prior to starting I/O. Default: true. | |
848 | .TP | |
849 | .BI sync \fR=\fPbool | |
850 | Use synchronous I/O for buffered writes. For the majority of I/O engines, | |
d1429b5c | 851 | this means using O_SYNC. Default: false. |
d60e92d1 AC |
852 | .TP |
853 | .BI iomem \fR=\fPstr "\fR,\fP mem" \fR=\fPstr | |
854 | Allocation method for I/O unit buffer. Allowed values are: | |
855 | .RS | |
856 | .RS | |
857 | .TP | |
858 | .B malloc | |
ccc2b328 | 859 | Allocate memory with \fBmalloc\fR\|(3). |
d60e92d1 AC |
860 | .TP |
861 | .B shm | |
ccc2b328 | 862 | Use shared memory buffers allocated through \fBshmget\fR\|(2). |
d60e92d1 AC |
863 | .TP |
864 | .B shmhuge | |
865 | Same as \fBshm\fR, but use huge pages as backing. | |
866 | .TP | |
867 | .B mmap | |
ccc2b328 | 868 | Use \fBmmap\fR\|(2) for allocation. Uses anonymous memory unless a filename |
d60e92d1 AC |
869 | is given after the option in the format `:\fIfile\fR'. |
870 | .TP | |
871 | .B mmaphuge | |
872 | Same as \fBmmap\fR, but use huge files as backing. | |
873 | .RE | |
874 | .P | |
875 | The amount of memory allocated is the maximum allowed \fBblocksize\fR for the | |
876 | job multiplied by \fBiodepth\fR. For \fBshmhuge\fR or \fBmmaphuge\fR to work, | |
877 | the system must have free huge pages allocated. \fBmmaphuge\fR also needs to | |
2e266ba6 JA |
878 | have hugetlbfs mounted, and \fIfile\fR must point there. At least on Linux, |
879 | huge pages must be manually allocated. See \fB/proc/sys/vm/nr_hugehages\fR | |
880 | and the documentation for that. Normally you just need to echo an appropriate | |
881 | number, eg echoing 8 will ensure that the OS has 8 huge pages ready for | |
882 | use. | |
d60e92d1 AC |
883 | .RE |
884 | .TP | |
d392365e | 885 | .BI iomem_align \fR=\fPint "\fR,\fP mem_align" \fR=\fPint |
cecbfd47 | 886 | This indicates the memory alignment of the IO memory buffers. Note that the |
d529ee19 JA |
887 | given alignment is applied to the first IO unit buffer, if using \fBiodepth\fR |
888 | the alignment of the following buffers are given by the \fBbs\fR used. In | |
889 | other words, if using a \fBbs\fR that is a multiple of the page sized in the | |
890 | system, all buffers will be aligned to this value. If using a \fBbs\fR that | |
891 | is not page aligned, the alignment of subsequent IO memory buffers is the | |
892 | sum of the \fBiomem_align\fR and \fBbs\fR used. | |
893 | .TP | |
f7fa2653 | 894 | .BI hugepage\-size \fR=\fPint |
d60e92d1 | 895 | Defines the size of a huge page. Must be at least equal to the system setting. |
b22989b9 | 896 | Should be a multiple of 1MB. Default: 4MB. |
d60e92d1 AC |
897 | .TP |
898 | .B exitall | |
899 | Terminate all jobs when one finishes. Default: wait for each job to finish. | |
900 | .TP | |
901 | .BI bwavgtime \fR=\fPint | |
902 | Average bandwidth calculations over the given time in milliseconds. Default: | |
903 | 500ms. | |
904 | .TP | |
c8eeb9df JA |
905 | .BI iopsavgtime \fR=\fPint |
906 | Average IOPS calculations over the given time in milliseconds. Default: | |
907 | 500ms. | |
908 | .TP | |
d60e92d1 | 909 | .BI create_serialize \fR=\fPbool |
d1429b5c | 910 | If true, serialize file creation for the jobs. Default: true. |
d60e92d1 AC |
911 | .TP |
912 | .BI create_fsync \fR=\fPbool | |
ccc2b328 | 913 | \fBfsync\fR\|(2) data file after creation. Default: true. |
d60e92d1 | 914 | .TP |
6b7f6851 JA |
915 | .BI create_on_open \fR=\fPbool |
916 | If true, the files are not created until they are opened for IO by the job. | |
917 | .TP | |
25460cf6 JA |
918 | .BI create_only \fR=\fPbool |
919 | If true, fio will only run the setup phase of the job. If files need to be | |
920 | laid out or updated on disk, only that will be done. The actual job contents | |
921 | are not executed. | |
922 | .TP | |
e9f48479 JA |
923 | .BI pre_read \fR=\fPbool |
924 | If this is given, files will be pre-read into memory before starting the given | |
925 | IO operation. This will also clear the \fR \fBinvalidate\fR flag, since it is | |
9c0d2241 JA |
926 | pointless to pre-read and then drop the cache. This will only work for IO |
927 | engines that are seekable, since they allow you to read the same data | |
928 | multiple times. Thus it will not work on eg network or splice IO. | |
e9f48479 | 929 | .TP |
d60e92d1 AC |
930 | .BI unlink \fR=\fPbool |
931 | Unlink job files when done. Default: false. | |
932 | .TP | |
933 | .BI loops \fR=\fPint | |
934 | Specifies the number of iterations (runs of the same workload) of this job. | |
935 | Default: 1. | |
936 | .TP | |
5e4c7118 JA |
937 | .BI verify_only \fR=\fPbool |
938 | Do not perform the specified workload, only verify data still matches previous | |
939 | invocation of this workload. This option allows one to check data multiple | |
940 | times at a later date without overwriting it. This option makes sense only for | |
941 | workloads that write data, and does not support workloads with the | |
942 | \fBtime_based\fR option set. | |
943 | .TP | |
d60e92d1 AC |
944 | .BI do_verify \fR=\fPbool |
945 | Run the verify phase after a write phase. Only valid if \fBverify\fR is set. | |
946 | Default: true. | |
947 | .TP | |
948 | .BI verify \fR=\fPstr | |
949 | Method of verifying file contents after each iteration of the job. Allowed | |
950 | values are: | |
951 | .RS | |
952 | .RS | |
953 | .TP | |
b892dc08 | 954 | .B md5 crc16 crc32 crc32c crc32c-intel crc64 crc7 sha256 sha512 sha1 |
0539d758 JA |
955 | Store appropriate checksum in the header of each block. crc32c-intel is |
956 | hardware accelerated SSE4.2 driven, falls back to regular crc32c if | |
957 | not supported by the system. | |
d60e92d1 AC |
958 | .TP |
959 | .B meta | |
960 | Write extra information about each I/O (timestamp, block number, etc.). The | |
996093bb | 961 | block number is verified. See \fBverify_pattern\fR as well. |
d60e92d1 AC |
962 | .TP |
963 | .B null | |
964 | Pretend to verify. Used for testing internals. | |
965 | .RE | |
b892dc08 JA |
966 | |
967 | This option can be used for repeated burn-in tests of a system to make sure | |
968 | that the written data is also correctly read back. If the data direction given | |
969 | is a read or random read, fio will assume that it should verify a previously | |
970 | written file. If the data direction includes any form of write, the verify will | |
971 | be of the newly written data. | |
d60e92d1 AC |
972 | .RE |
973 | .TP | |
5c9323fb | 974 | .BI verifysort \fR=\fPbool |
d60e92d1 AC |
975 | If true, written verify blocks are sorted if \fBfio\fR deems it to be faster to |
976 | read them back in a sorted manner. Default: true. | |
977 | .TP | |
fa769d44 SW |
978 | .BI verifysort_nr \fR=\fPint |
979 | Pre-load and sort verify blocks for a read workload. | |
980 | .TP | |
f7fa2653 | 981 | .BI verify_offset \fR=\fPint |
d60e92d1 | 982 | Swap the verification header with data somewhere else in the block before |
d1429b5c | 983 | writing. It is swapped back before verifying. |
d60e92d1 | 984 | .TP |
f7fa2653 | 985 | .BI verify_interval \fR=\fPint |
d60e92d1 AC |
986 | Write the verification header for this number of bytes, which should divide |
987 | \fBblocksize\fR. Default: \fBblocksize\fR. | |
988 | .TP | |
996093bb JA |
989 | .BI verify_pattern \fR=\fPstr |
990 | If set, fio will fill the io buffers with this pattern. Fio defaults to filling | |
991 | with totally random bytes, but sometimes it's interesting to fill with a known | |
992 | pattern for io verification purposes. Depending on the width of the pattern, | |
993 | fio will fill 1/2/3/4 bytes of the buffer at the time(it can be either a | |
994 | decimal or a hex number). The verify_pattern if larger than a 32-bit quantity | |
995 | has to be a hex number that starts with either "0x" or "0X". Use with | |
996 | \fBverify\fP=meta. | |
997 | .TP | |
d60e92d1 AC |
998 | .BI verify_fatal \fR=\fPbool |
999 | If true, exit the job on the first observed verification failure. Default: | |
1000 | false. | |
1001 | .TP | |
b463e936 JA |
1002 | .BI verify_dump \fR=\fPbool |
1003 | If set, dump the contents of both the original data block and the data block we | |
1004 | read off disk to files. This allows later analysis to inspect just what kind of | |
ef71e317 | 1005 | data corruption occurred. Off by default. |
b463e936 | 1006 | .TP |
e8462bd8 JA |
1007 | .BI verify_async \fR=\fPint |
1008 | Fio will normally verify IO inline from the submitting thread. This option | |
1009 | takes an integer describing how many async offload threads to create for IO | |
1010 | verification instead, causing fio to offload the duty of verifying IO contents | |
c85c324c JA |
1011 | to one or more separate threads. If using this offload option, even sync IO |
1012 | engines can benefit from using an \fBiodepth\fR setting higher than 1, as it | |
1013 | allows them to have IO in flight while verifies are running. | |
e8462bd8 JA |
1014 | .TP |
1015 | .BI verify_async_cpus \fR=\fPstr | |
1016 | Tell fio to set the given CPU affinity on the async IO verification threads. | |
1017 | See \fBcpus_allowed\fP for the format used. | |
1018 | .TP | |
6f87418f JA |
1019 | .BI verify_backlog \fR=\fPint |
1020 | Fio will normally verify the written contents of a job that utilizes verify | |
1021 | once that job has completed. In other words, everything is written then | |
1022 | everything is read back and verified. You may want to verify continually | |
1023 | instead for a variety of reasons. Fio stores the meta data associated with an | |
1024 | IO block in memory, so for large verify workloads, quite a bit of memory would | |
092f707f DN |
1025 | be used up holding this meta data. If this option is enabled, fio will write |
1026 | only N blocks before verifying these blocks. | |
6f87418f JA |
1027 | .TP |
1028 | .BI verify_backlog_batch \fR=\fPint | |
1029 | Control how many blocks fio will verify if verify_backlog is set. If not set, | |
1030 | will default to the value of \fBverify_backlog\fR (meaning the entire queue is | |
092f707f DN |
1031 | read back and verified). If \fBverify_backlog_batch\fR is less than |
1032 | \fBverify_backlog\fR then not all blocks will be verified, if | |
1033 | \fBverify_backlog_batch\fR is larger than \fBverify_backlog\fR, some blocks | |
1034 | will be verified more than once. | |
6f87418f | 1035 | .TP |
fa769d44 SW |
1036 | .BI trim_percentage \fR=\fPint |
1037 | Number of verify blocks to discard/trim. | |
1038 | .TP | |
1039 | .BI trim_verify_zero \fR=\fPbool | |
1040 | Verify that trim/discarded blocks are returned as zeroes. | |
1041 | .TP | |
1042 | .BI trim_backlog \fR=\fPint | |
1043 | Trim after this number of blocks are written. | |
1044 | .TP | |
1045 | .BI trim_backlog_batch \fR=\fPint | |
1046 | Trim this number of IO blocks. | |
1047 | .TP | |
1048 | .BI experimental_verify \fR=\fPbool | |
1049 | Enable experimental verification. | |
1050 | .TP | |
d392365e | 1051 | .B stonewall "\fR,\fP wait_for_previous" |
5982a925 | 1052 | Wait for preceding jobs in the job file to exit before starting this one. |
d60e92d1 AC |
1053 | \fBstonewall\fR implies \fBnew_group\fR. |
1054 | .TP | |
1055 | .B new_group | |
1056 | Start a new reporting group. If not given, all jobs in a file will be part | |
1057 | of the same reporting group, unless separated by a stonewall. | |
1058 | .TP | |
1059 | .BI numjobs \fR=\fPint | |
1060 | Number of clones (processes/threads performing the same workload) of this job. | |
1061 | Default: 1. | |
1062 | .TP | |
1063 | .B group_reporting | |
1064 | If set, display per-group reports instead of per-job when \fBnumjobs\fR is | |
1065 | specified. | |
1066 | .TP | |
1067 | .B thread | |
1068 | Use threads created with \fBpthread_create\fR\|(3) instead of processes created | |
1069 | with \fBfork\fR\|(2). | |
1070 | .TP | |
f7fa2653 | 1071 | .BI zonesize \fR=\fPint |
d60e92d1 AC |
1072 | Divide file into zones of the specified size in bytes. See \fBzoneskip\fR. |
1073 | .TP | |
fa769d44 SW |
1074 | .BI zonerange \fR=\fPint |
1075 | Give size of an IO zone. See \fBzoneskip\fR. | |
1076 | .TP | |
f7fa2653 | 1077 | .BI zoneskip \fR=\fPint |
d1429b5c | 1078 | Skip the specified number of bytes when \fBzonesize\fR bytes of data have been |
d60e92d1 AC |
1079 | read. |
1080 | .TP | |
1081 | .BI write_iolog \fR=\fPstr | |
5b42a488 SH |
1082 | Write the issued I/O patterns to the specified file. Specify a separate file |
1083 | for each job, otherwise the iologs will be interspersed and the file may be | |
1084 | corrupt. | |
d60e92d1 AC |
1085 | .TP |
1086 | .BI read_iolog \fR=\fPstr | |
1087 | Replay the I/O patterns contained in the specified file generated by | |
1088 | \fBwrite_iolog\fR, or may be a \fBblktrace\fR binary file. | |
1089 | .TP | |
64bbb865 DN |
1090 | .BI replay_no_stall \fR=\fPint |
1091 | While replaying I/O patterns using \fBread_iolog\fR the default behavior | |
1092 | attempts to respect timing information between I/Os. Enabling | |
1093 | \fBreplay_no_stall\fR causes I/Os to be replayed as fast as possible while | |
1094 | still respecting ordering. | |
1095 | .TP | |
d1c46c04 DN |
1096 | .BI replay_redirect \fR=\fPstr |
1097 | While replaying I/O patterns using \fBread_iolog\fR the default behavior | |
1098 | is to replay the IOPS onto the major/minor device that each IOP was recorded | |
1099 | from. Setting \fBreplay_redirect\fR causes all IOPS to be replayed onto the | |
1100 | single specified device regardless of the device it was recorded from. | |
1101 | .TP | |
836bad52 | 1102 | .BI write_bw_log \fR=\fPstr |
901bb994 JA |
1103 | If given, write a bandwidth log of the jobs in this job file. Can be used to |
1104 | store data of the bandwidth of the jobs in their lifetime. The included | |
1105 | fio_generate_plots script uses gnuplot to turn these text files into nice | |
26b26fca | 1106 | graphs. See \fBwrite_lat_log\fR for behaviour of given filename. For this |
901bb994 | 1107 | option, the postfix is _bw.log. |
d60e92d1 | 1108 | .TP |
836bad52 | 1109 | .BI write_lat_log \fR=\fPstr |
901bb994 JA |
1110 | Same as \fBwrite_bw_log\fR, but writes I/O completion latencies. If no |
1111 | filename is given with this option, the default filename of "jobname_type.log" | |
1112 | is used. Even if the filename is given, fio will still append the type of log. | |
1113 | .TP | |
c8eeb9df JA |
1114 | .BI write_iops_log \fR=\fPstr |
1115 | Same as \fBwrite_bw_log\fR, but writes IOPS. If no filename is given with this | |
1116 | option, the default filename of "jobname_type.log" is used. Even if the | |
1117 | filename is given, fio will still append the type of log. | |
1118 | .TP | |
b8bc8cba JA |
1119 | .BI log_avg_msec \fR=\fPint |
1120 | By default, fio will log an entry in the iops, latency, or bw log for every | |
1121 | IO that completes. When writing to the disk log, that can quickly grow to a | |
1122 | very large size. Setting this option makes fio average the each log entry | |
1123 | over the specified period of time, reducing the resolution of the log. | |
1124 | Defaults to 0. | |
1125 | .TP | |
836bad52 | 1126 | .BI disable_lat \fR=\fPbool |
02af0988 | 1127 | Disable measurements of total latency numbers. Useful only for cutting |
ccc2b328 | 1128 | back the number of calls to \fBgettimeofday\fR\|(2), as that does impact performance at |
901bb994 JA |
1129 | really high IOPS rates. Note that to really get rid of a large amount of these |
1130 | calls, this option must be used with disable_slat and disable_bw as well. | |
1131 | .TP | |
836bad52 | 1132 | .BI disable_clat \fR=\fPbool |
c95f9daf | 1133 | Disable measurements of completion latency numbers. See \fBdisable_lat\fR. |
02af0988 | 1134 | .TP |
836bad52 | 1135 | .BI disable_slat \fR=\fPbool |
02af0988 | 1136 | Disable measurements of submission latency numbers. See \fBdisable_lat\fR. |
901bb994 | 1137 | .TP |
836bad52 | 1138 | .BI disable_bw_measurement \fR=\fPbool |
02af0988 | 1139 | Disable measurements of throughput/bandwidth numbers. See \fBdisable_lat\fR. |
d60e92d1 | 1140 | .TP |
f7fa2653 | 1141 | .BI lockmem \fR=\fPint |
d60e92d1 | 1142 | Pin the specified amount of memory with \fBmlock\fR\|(2). Can be used to |
81c6b6cd | 1143 | simulate a smaller amount of memory. The amount specified is per worker. |
d60e92d1 AC |
1144 | .TP |
1145 | .BI exec_prerun \fR=\fPstr | |
1146 | Before running the job, execute the specified command with \fBsystem\fR\|(3). | |
ce486495 EV |
1147 | .RS |
1148 | Output is redirected in a file called \fBjobname.prerun.txt\fR | |
1149 | .RE | |
d60e92d1 AC |
1150 | .TP |
1151 | .BI exec_postrun \fR=\fPstr | |
1152 | Same as \fBexec_prerun\fR, but the command is executed after the job completes. | |
ce486495 EV |
1153 | .RS |
1154 | Output is redirected in a file called \fBjobname.postrun.txt\fR | |
1155 | .RE | |
d60e92d1 AC |
1156 | .TP |
1157 | .BI ioscheduler \fR=\fPstr | |
1158 | Attempt to switch the device hosting the file to the specified I/O scheduler. | |
1159 | .TP | |
1160 | .BI cpuload \fR=\fPint | |
1161 | If the job is a CPU cycle-eater, attempt to use the specified percentage of | |
1162 | CPU cycles. | |
1163 | .TP | |
1164 | .BI cpuchunks \fR=\fPint | |
1165 | If the job is a CPU cycle-eater, split the load into cycles of the | |
1166 | given time in milliseconds. | |
1167 | .TP | |
1168 | .BI disk_util \fR=\fPbool | |
d1429b5c | 1169 | Generate disk utilization statistics if the platform supports it. Default: true. |
901bb994 | 1170 | .TP |
23893646 JA |
1171 | .BI clocksource \fR=\fPstr |
1172 | Use the given clocksource as the base of timing. The supported options are: | |
1173 | .RS | |
1174 | .TP | |
1175 | .B gettimeofday | |
ccc2b328 | 1176 | \fBgettimeofday\fR\|(2) |
23893646 JA |
1177 | .TP |
1178 | .B clock_gettime | |
ccc2b328 | 1179 | \fBclock_gettime\fR\|(2) |
23893646 JA |
1180 | .TP |
1181 | .B cpu | |
1182 | Internal CPU clock source | |
1183 | .TP | |
1184 | .RE | |
1185 | .P | |
1186 | \fBcpu\fR is the preferred clocksource if it is reliable, as it is very fast | |
1187 | (and fio is heavy on time calls). Fio will automatically use this clocksource | |
1188 | if it's supported and considered reliable on the system it is running on, | |
1189 | unless another clocksource is specifically set. For x86/x86-64 CPUs, this | |
1190 | means supporting TSC Invariant. | |
1191 | .TP | |
901bb994 | 1192 | .BI gtod_reduce \fR=\fPbool |
ccc2b328 | 1193 | Enable all of the \fBgettimeofday\fR\|(2) reducing options (disable_clat, disable_slat, |
901bb994 | 1194 | disable_bw) plus reduce precision of the timeout somewhat to really shrink the |
ccc2b328 | 1195 | \fBgettimeofday\fR\|(2) call count. With this option enabled, we only do about 0.4% of |
901bb994 JA |
1196 | the gtod() calls we would have done if all time keeping was enabled. |
1197 | .TP | |
1198 | .BI gtod_cpu \fR=\fPint | |
1199 | Sometimes it's cheaper to dedicate a single thread of execution to just getting | |
1200 | the current time. Fio (and databases, for instance) are very intensive on | |
ccc2b328 | 1201 | \fBgettimeofday\fR\|(2) calls. With this option, you can set one CPU aside for doing |
901bb994 JA |
1202 | nothing but logging current time to a shared memory location. Then the other |
1203 | threads/processes that run IO workloads need only copy that segment, instead of | |
ccc2b328 | 1204 | entering the kernel with a \fBgettimeofday\fR\|(2) call. The CPU set aside for doing |
901bb994 JA |
1205 | these time calls will be excluded from other uses. Fio will manually clear it |
1206 | from the CPU mask of other jobs. | |
f2bba182 | 1207 | .TP |
8b28bd41 DM |
1208 | .BI ignore_error \fR=\fPstr |
1209 | Sometimes you want to ignore some errors during test in that case you can specify | |
1210 | error list for each error type. | |
1211 | .br | |
1212 | ignore_error=READ_ERR_LIST,WRITE_ERR_LIST,VERIFY_ERR_LIST | |
1213 | .br | |
1214 | errors for given error type is separated with ':'. | |
1215 | Error may be symbol ('ENOSPC', 'ENOMEM') or an integer. | |
1216 | .br | |
1217 | Example: ignore_error=EAGAIN,ENOSPC:122 . | |
1218 | .br | |
1219 | This option will ignore EAGAIN from READ, and ENOSPC and 122(EDQUOT) from WRITE. | |
1220 | .TP | |
1221 | .BI error_dump \fR=\fPbool | |
1222 | If set dump every error even if it is non fatal, true by default. If disabled | |
1223 | only fatal error will be dumped | |
1224 | .TP | |
fa769d44 SW |
1225 | .BI profile \fR=\fPstr |
1226 | Select a specific builtin performance test. | |
1227 | .TP | |
a696fa2a JA |
1228 | .BI cgroup \fR=\fPstr |
1229 | Add job to this control group. If it doesn't exist, it will be created. | |
6adb38a1 JA |
1230 | The system must have a mounted cgroup blkio mount point for this to work. If |
1231 | your system doesn't have it mounted, you can do so with: | |
1232 | ||
5982a925 | 1233 | # mount \-t cgroup \-o blkio none /cgroup |
a696fa2a JA |
1234 | .TP |
1235 | .BI cgroup_weight \fR=\fPint | |
1236 | Set the weight of the cgroup to this value. See the documentation that comes | |
1237 | with the kernel, allowed values are in the range of 100..1000. | |
e0b0d892 | 1238 | .TP |
7de87099 VG |
1239 | .BI cgroup_nodelete \fR=\fPbool |
1240 | Normally fio will delete the cgroups it has created after the job completion. | |
1241 | To override this behavior and to leave cgroups around after the job completion, | |
1242 | set cgroup_nodelete=1. This can be useful if one wants to inspect various | |
1243 | cgroup files after job completion. Default: false | |
1244 | .TP | |
e0b0d892 JA |
1245 | .BI uid \fR=\fPint |
1246 | Instead of running as the invoking user, set the user ID to this value before | |
1247 | the thread/process does any work. | |
1248 | .TP | |
1249 | .BI gid \fR=\fPint | |
1250 | Set group ID, see \fBuid\fR. | |
83349190 | 1251 | .TP |
fa769d44 SW |
1252 | .BI unit_base \fR=\fPint |
1253 | Base unit for reporting. Allowed values are: | |
1254 | .RS | |
1255 | .TP | |
1256 | .B 0 | |
1257 | Use auto-detection (default). | |
1258 | .TP | |
1259 | .B 8 | |
1260 | Byte based. | |
1261 | .TP | |
1262 | .B 1 | |
1263 | Bit based. | |
1264 | .RE | |
1265 | .P | |
1266 | .TP | |
9e684a49 DE |
1267 | .BI flow_id \fR=\fPint |
1268 | The ID of the flow. If not specified, it defaults to being a global flow. See | |
1269 | \fBflow\fR. | |
1270 | .TP | |
1271 | .BI flow \fR=\fPint | |
1272 | Weight in token-based flow control. If this value is used, then there is a | |
1273 | \fBflow counter\fR which is used to regulate the proportion of activity between | |
1274 | two or more jobs. fio attempts to keep this flow counter near zero. The | |
1275 | \fBflow\fR parameter stands for how much should be added or subtracted to the | |
1276 | flow counter on each iteration of the main I/O loop. That is, if one job has | |
1277 | \fBflow=8\fR and another job has \fBflow=-1\fR, then there will be a roughly | |
1278 | 1:8 ratio in how much one runs vs the other. | |
1279 | .TP | |
1280 | .BI flow_watermark \fR=\fPint | |
1281 | The maximum value that the absolute value of the flow counter is allowed to | |
1282 | reach before the job must wait for a lower value of the counter. | |
1283 | .TP | |
1284 | .BI flow_sleep \fR=\fPint | |
1285 | The period of time, in microseconds, to wait after the flow watermark has been | |
1286 | exceeded before retrying operations | |
1287 | .TP | |
83349190 YH |
1288 | .BI clat_percentiles \fR=\fPbool |
1289 | Enable the reporting of percentiles of completion latencies. | |
1290 | .TP | |
1291 | .BI percentile_list \fR=\fPfloat_list | |
1292 | Overwrite the default list of percentiles for completion | |
1293 | latencies. Each number is a floating number in the range (0,100], and | |
1294 | the maximum length of the list is 20. Use ':' to separate the | |
3eb07285 | 1295 | numbers. For example, \-\-percentile_list=99.5:99.9 will cause fio to |
83349190 YH |
1296 | report the values of completion latency below which 99.5% and 99.9% of |
1297 | the observed latencies fell, respectively. | |
de890a1e SL |
1298 | .SS "Ioengine Parameters List" |
1299 | Some parameters are only valid when a specific ioengine is in use. These are | |
1300 | used identically to normal parameters, with the caveat that when used on the | |
1301 | command line, the must come after the ioengine that defines them is selected. | |
1302 | .TP | |
e4585935 JA |
1303 | .BI (cpu)cpuload \fR=\fPint |
1304 | Attempt to use the specified percentage of CPU cycles. | |
1305 | .TP | |
1306 | .BI (cpu)cpuchunks \fR=\fPint | |
1307 | Split the load into cycles of the given time. In microseconds. | |
1308 | .TP | |
de890a1e SL |
1309 | .BI (libaio)userspace_reap |
1310 | Normally, with the libaio engine in use, fio will use | |
1311 | the io_getevents system call to reap newly returned events. | |
1312 | With this flag turned on, the AIO ring will be read directly | |
1313 | from user-space to reap events. The reaping mode is only | |
1314 | enabled when polling for a minimum of 0 events (eg when | |
1315 | iodepth_batch_complete=0). | |
1316 | .TP | |
1317 | .BI (net,netsplice)hostname \fR=\fPstr | |
1318 | The host name or IP address to use for TCP or UDP based IO. | |
1319 | If the job is a TCP listener or UDP reader, the hostname is not | |
b511c9aa | 1320 | used and must be omitted unless it is a valid UDP multicast address. |
de890a1e SL |
1321 | .TP |
1322 | .BI (net,netsplice)port \fR=\fPint | |
1323 | The TCP or UDP port to bind to or connect to. | |
1324 | .TP | |
b93b6a2e SB |
1325 | .BI (net,netsplice)interface \fR=\fPstr |
1326 | The IP address of the network interface used to send or receive UDP multicast | |
1327 | packets. | |
1328 | .TP | |
d3a623de SB |
1329 | .BI (net,netsplice)ttl \fR=\fPint |
1330 | Time-to-live value for outgoing UDP multicast packets. Default: 1 | |
1331 | .TP | |
1d360ffb JA |
1332 | .BI (net,netsplice)nodelay \fR=\fPbool |
1333 | Set TCP_NODELAY on TCP connections. | |
1334 | .TP | |
de890a1e SL |
1335 | .BI (net,netsplice)protocol \fR=\fPstr "\fR,\fP proto" \fR=\fPstr |
1336 | The network protocol to use. Accepted values are: | |
1337 | .RS | |
1338 | .RS | |
1339 | .TP | |
1340 | .B tcp | |
1341 | Transmission control protocol | |
1342 | .TP | |
49ccb8c1 JA |
1343 | .B tcpv6 |
1344 | Transmission control protocol V6 | |
1345 | .TP | |
de890a1e | 1346 | .B udp |
f5cc3d0e | 1347 | User datagram protocol |
de890a1e | 1348 | .TP |
49ccb8c1 JA |
1349 | .B udpv6 |
1350 | User datagram protocol V6 | |
1351 | .TP | |
de890a1e SL |
1352 | .B unix |
1353 | UNIX domain socket | |
1354 | .RE | |
1355 | .P | |
1356 | When the protocol is TCP or UDP, the port must also be given, | |
1357 | as well as the hostname if the job is a TCP listener or UDP | |
1358 | reader. For unix sockets, the normal filename option should be | |
1359 | used and the port is invalid. | |
1360 | .RE | |
1361 | .TP | |
1362 | .BI (net,netsplice)listen | |
1363 | For TCP network connections, tell fio to listen for incoming | |
1364 | connections rather than initiating an outgoing connection. The | |
1365 | hostname must be omitted if this option is used. | |
d54fce84 | 1366 | .TP |
7aeb1e94 | 1367 | .BI (net, pingpong) \fR=\fPbool |
cecbfd47 | 1368 | Normally a network writer will just continue writing data, and a network reader |
7aeb1e94 JA |
1369 | will just consume packages. If pingpong=1 is set, a writer will send its normal |
1370 | payload to the reader, then wait for the reader to send the same payload back. | |
1371 | This allows fio to measure network latencies. The submission and completion | |
1372 | latencies then measure local time spent sending or receiving, and the | |
1373 | completion latency measures how long it took for the other end to receive and | |
b511c9aa SB |
1374 | send back. For UDP multicast traffic pingpong=1 should only be set for a single |
1375 | reader when multiple readers are listening to the same address. | |
7aeb1e94 | 1376 | .TP |
d54fce84 DM |
1377 | .BI (e4defrag,donorname) \fR=\fPstr |
1378 | File will be used as a block donor (swap extents between files) | |
1379 | .TP | |
1380 | .BI (e4defrag,inplace) \fR=\fPint | |
1381 | Configure donor file block allocation strategy | |
1382 | .RS | |
1383 | .BI 0(default) : | |
1384 | Preallocate donor's file on init | |
1385 | .TP | |
1386 | .BI 1: | |
cecbfd47 | 1387 | allocate space immediately inside defragment event, and free right after event |
d54fce84 | 1388 | .RE |
d60e92d1 | 1389 | .SH OUTPUT |
d1429b5c AC |
1390 | While running, \fBfio\fR will display the status of the created jobs. For |
1391 | example: | |
d60e92d1 | 1392 | .RS |
d1429b5c | 1393 | .P |
d60e92d1 AC |
1394 | Threads: 1: [_r] [24.8% done] [ 13509/ 8334 kb/s] [eta 00h:01m:31s] |
1395 | .RE | |
1396 | .P | |
d1429b5c AC |
1397 | The characters in the first set of brackets denote the current status of each |
1398 | threads. The possible values are: | |
1399 | .P | |
1400 | .PD 0 | |
d60e92d1 AC |
1401 | .RS |
1402 | .TP | |
1403 | .B P | |
1404 | Setup but not started. | |
1405 | .TP | |
1406 | .B C | |
1407 | Thread created. | |
1408 | .TP | |
1409 | .B I | |
1410 | Initialized, waiting. | |
1411 | .TP | |
1412 | .B R | |
1413 | Running, doing sequential reads. | |
1414 | .TP | |
1415 | .B r | |
1416 | Running, doing random reads. | |
1417 | .TP | |
1418 | .B W | |
1419 | Running, doing sequential writes. | |
1420 | .TP | |
1421 | .B w | |
1422 | Running, doing random writes. | |
1423 | .TP | |
1424 | .B M | |
1425 | Running, doing mixed sequential reads/writes. | |
1426 | .TP | |
1427 | .B m | |
1428 | Running, doing mixed random reads/writes. | |
1429 | .TP | |
1430 | .B F | |
1431 | Running, currently waiting for \fBfsync\fR\|(2). | |
1432 | .TP | |
1433 | .B V | |
1434 | Running, verifying written data. | |
1435 | .TP | |
1436 | .B E | |
1437 | Exited, not reaped by main thread. | |
1438 | .TP | |
1439 | .B \- | |
1440 | Exited, thread reaped. | |
1441 | .RE | |
d1429b5c | 1442 | .PD |
d60e92d1 AC |
1443 | .P |
1444 | The second set of brackets shows the estimated completion percentage of | |
1445 | the current group. The third set shows the read and write I/O rate, | |
1446 | respectively. Finally, the estimated run time of the job is displayed. | |
1447 | .P | |
1448 | When \fBfio\fR completes (or is interrupted by Ctrl-C), it will show data | |
1449 | for each thread, each group of threads, and each disk, in that order. | |
1450 | .P | |
1451 | Per-thread statistics first show the threads client number, group-id, and | |
1452 | error code. The remaining figures are as follows: | |
1453 | .RS | |
d60e92d1 AC |
1454 | .TP |
1455 | .B io | |
1456 | Number of megabytes of I/O performed. | |
1457 | .TP | |
1458 | .B bw | |
1459 | Average data rate (bandwidth). | |
1460 | .TP | |
1461 | .B runt | |
1462 | Threads run time. | |
1463 | .TP | |
1464 | .B slat | |
1465 | Submission latency minimum, maximum, average and standard deviation. This is | |
1466 | the time it took to submit the I/O. | |
1467 | .TP | |
1468 | .B clat | |
1469 | Completion latency minimum, maximum, average and standard deviation. This | |
1470 | is the time between submission and completion. | |
1471 | .TP | |
1472 | .B bw | |
1473 | Bandwidth minimum, maximum, percentage of aggregate bandwidth received, average | |
1474 | and standard deviation. | |
1475 | .TP | |
1476 | .B cpu | |
1477 | CPU usage statistics. Includes user and system time, number of context switches | |
1478 | this thread went through and number of major and minor page faults. | |
1479 | .TP | |
1480 | .B IO depths | |
1481 | Distribution of I/O depths. Each depth includes everything less than (or equal) | |
1482 | to it, but greater than the previous depth. | |
1483 | .TP | |
1484 | .B IO issued | |
1485 | Number of read/write requests issued, and number of short read/write requests. | |
1486 | .TP | |
1487 | .B IO latencies | |
1488 | Distribution of I/O completion latencies. The numbers follow the same pattern | |
1489 | as \fBIO depths\fR. | |
1490 | .RE | |
d60e92d1 AC |
1491 | .P |
1492 | The group statistics show: | |
d1429b5c | 1493 | .PD 0 |
d60e92d1 AC |
1494 | .RS |
1495 | .TP | |
1496 | .B io | |
1497 | Number of megabytes I/O performed. | |
1498 | .TP | |
1499 | .B aggrb | |
1500 | Aggregate bandwidth of threads in the group. | |
1501 | .TP | |
1502 | .B minb | |
1503 | Minimum average bandwidth a thread saw. | |
1504 | .TP | |
1505 | .B maxb | |
1506 | Maximum average bandwidth a thread saw. | |
1507 | .TP | |
1508 | .B mint | |
d1429b5c | 1509 | Shortest runtime of threads in the group. |
d60e92d1 AC |
1510 | .TP |
1511 | .B maxt | |
1512 | Longest runtime of threads in the group. | |
1513 | .RE | |
d1429b5c | 1514 | .PD |
d60e92d1 AC |
1515 | .P |
1516 | Finally, disk statistics are printed with reads first: | |
d1429b5c | 1517 | .PD 0 |
d60e92d1 AC |
1518 | .RS |
1519 | .TP | |
1520 | .B ios | |
1521 | Number of I/Os performed by all groups. | |
1522 | .TP | |
1523 | .B merge | |
1524 | Number of merges in the I/O scheduler. | |
1525 | .TP | |
1526 | .B ticks | |
1527 | Number of ticks we kept the disk busy. | |
1528 | .TP | |
1529 | .B io_queue | |
1530 | Total time spent in the disk queue. | |
1531 | .TP | |
1532 | .B util | |
1533 | Disk utilization. | |
1534 | .RE | |
d1429b5c | 1535 | .PD |
8423bd11 JA |
1536 | .P |
1537 | It is also possible to get fio to dump the current output while it is | |
1538 | running, without terminating the job. To do that, send fio the \fBUSR1\fR | |
1539 | signal. | |
d60e92d1 AC |
1540 | .SH TERSE OUTPUT |
1541 | If the \fB\-\-minimal\fR option is given, the results will be printed in a | |
562c2d2f DN |
1542 | semicolon-delimited format suitable for scripted use - a job description |
1543 | (if provided) follows on a new line. Note that the first | |
525c2bfa JA |
1544 | number in the line is the version number. If the output has to be changed |
1545 | for some reason, this number will be incremented by 1 to signify that | |
1546 | change. The fields are: | |
d60e92d1 AC |
1547 | .P |
1548 | .RS | |
5e726d0a | 1549 | .B terse version, fio version, jobname, groupid, error |
d60e92d1 AC |
1550 | .P |
1551 | Read status: | |
1552 | .RS | |
312b4af2 | 1553 | .B Total I/O \fR(KB)\fP, bandwidth \fR(KB/s)\fP, IOPS, runtime \fR(ms)\fP |
d60e92d1 AC |
1554 | .P |
1555 | Submission latency: | |
1556 | .RS | |
1557 | .B min, max, mean, standard deviation | |
1558 | .RE | |
1559 | Completion latency: | |
1560 | .RS | |
1561 | .B min, max, mean, standard deviation | |
1562 | .RE | |
1db92cb6 JA |
1563 | Completion latency percentiles (20 fields): |
1564 | .RS | |
1565 | .B Xth percentile=usec | |
1566 | .RE | |
525c2bfa JA |
1567 | Total latency: |
1568 | .RS | |
1569 | .B min, max, mean, standard deviation | |
1570 | .RE | |
d60e92d1 AC |
1571 | Bandwidth: |
1572 | .RS | |
1573 | .B min, max, aggregate percentage of total, mean, standard deviation | |
1574 | .RE | |
1575 | .RE | |
1576 | .P | |
1577 | Write status: | |
1578 | .RS | |
312b4af2 | 1579 | .B Total I/O \fR(KB)\fP, bandwidth \fR(KB/s)\fP, IOPS, runtime \fR(ms)\fP |
d60e92d1 AC |
1580 | .P |
1581 | Submission latency: | |
1582 | .RS | |
1583 | .B min, max, mean, standard deviation | |
1584 | .RE | |
1585 | Completion latency: | |
1586 | .RS | |
1587 | .B min, max, mean, standard deviation | |
1588 | .RE | |
1db92cb6 JA |
1589 | Completion latency percentiles (20 fields): |
1590 | .RS | |
1591 | .B Xth percentile=usec | |
1592 | .RE | |
525c2bfa JA |
1593 | Total latency: |
1594 | .RS | |
1595 | .B min, max, mean, standard deviation | |
1596 | .RE | |
d60e92d1 AC |
1597 | Bandwidth: |
1598 | .RS | |
1599 | .B min, max, aggregate percentage of total, mean, standard deviation | |
1600 | .RE | |
1601 | .RE | |
1602 | .P | |
d1429b5c | 1603 | CPU usage: |
d60e92d1 | 1604 | .RS |
bd2626f0 | 1605 | .B user, system, context switches, major page faults, minor page faults |
d60e92d1 AC |
1606 | .RE |
1607 | .P | |
1608 | IO depth distribution: | |
1609 | .RS | |
1610 | .B <=1, 2, 4, 8, 16, 32, >=64 | |
1611 | .RE | |
1612 | .P | |
562c2d2f | 1613 | IO latency distribution: |
d60e92d1 | 1614 | .RS |
562c2d2f DN |
1615 | Microseconds: |
1616 | .RS | |
1617 | .B <=2, 4, 10, 20, 50, 100, 250, 500, 750, 1000 | |
1618 | .RE | |
1619 | Milliseconds: | |
1620 | .RS | |
1621 | .B <=2, 4, 10, 20, 50, 100, 250, 500, 750, 1000, 2000, >=2000 | |
1622 | .RE | |
1623 | .RE | |
1624 | .P | |
f2f788dd JA |
1625 | Disk utilization (1 for each disk used): |
1626 | .RS | |
1627 | .B name, read ios, write ios, read merges, write merges, read ticks, write ticks, read in-queue time, write in-queue time, disk utilization percentage | |
1628 | .RE | |
1629 | .P | |
5982a925 | 1630 | Error Info (dependent on continue_on_error, default off): |
562c2d2f DN |
1631 | .RS |
1632 | .B total # errors, first error code | |
d60e92d1 AC |
1633 | .RE |
1634 | .P | |
562c2d2f | 1635 | .B text description (if provided in config - appears on newline) |
d60e92d1 | 1636 | .RE |
49da1240 JA |
1637 | .SH CLIENT / SERVER |
1638 | Normally you would run fio as a stand-alone application on the machine | |
1639 | where the IO workload should be generated. However, it is also possible to | |
1640 | run the frontend and backend of fio separately. This makes it possible to | |
1641 | have a fio server running on the machine(s) where the IO workload should | |
1642 | be running, while controlling it from another machine. | |
1643 | ||
1644 | To start the server, you would do: | |
1645 | ||
1646 | \fBfio \-\-server=args\fR | |
1647 | ||
1648 | on that machine, where args defines what fio listens to. The arguments | |
811826be | 1649 | are of the form 'type:hostname or IP:port'. 'type' is either 'ip' (or ip4) |
20c67f10 MS |
1650 | for TCP/IP v4, 'ip6' for TCP/IP v6, or 'sock' for a local unix domain |
1651 | socket. 'hostname' is either a hostname or IP address, and 'port' is the port to | |
811826be | 1652 | listen to (only valid for TCP/IP, not a local socket). Some examples: |
49da1240 | 1653 | |
e01e9745 | 1654 | 1) fio \-\-server |
49da1240 JA |
1655 | |
1656 | Start a fio server, listening on all interfaces on the default port (8765). | |
1657 | ||
e01e9745 | 1658 | 2) fio \-\-server=ip:hostname,4444 |
49da1240 JA |
1659 | |
1660 | Start a fio server, listening on IP belonging to hostname and on port 4444. | |
1661 | ||
e01e9745 | 1662 | 3) fio \-\-server=ip6:::1,4444 |
811826be JA |
1663 | |
1664 | Start a fio server, listening on IPv6 localhost ::1 and on port 4444. | |
1665 | ||
e01e9745 | 1666 | 4) fio \-\-server=,4444 |
49da1240 JA |
1667 | |
1668 | Start a fio server, listening on all interfaces on port 4444. | |
1669 | ||
e01e9745 | 1670 | 5) fio \-\-server=1.2.3.4 |
49da1240 JA |
1671 | |
1672 | Start a fio server, listening on IP 1.2.3.4 on the default port. | |
1673 | ||
e01e9745 | 1674 | 6) fio \-\-server=sock:/tmp/fio.sock |
49da1240 JA |
1675 | |
1676 | Start a fio server, listening on the local socket /tmp/fio.sock. | |
1677 | ||
1678 | When a server is running, you can connect to it from a client. The client | |
1679 | is run with: | |
1680 | ||
e01e9745 | 1681 | fio \-\-local-args \-\-client=server \-\-remote-args <job file(s)> |
49da1240 | 1682 | |
e01e9745 MS |
1683 | where \-\-local-args are arguments that are local to the client where it is |
1684 | running, 'server' is the connect string, and \-\-remote-args and <job file(s)> | |
49da1240 JA |
1685 | are sent to the server. The 'server' string follows the same format as it |
1686 | does on the server side, to allow IP/hostname/socket and port strings. | |
1687 | You can connect to multiple clients as well, to do that you could run: | |
1688 | ||
e01e9745 | 1689 | fio \-\-client=server2 \-\-client=server2 <job file(s)> |
d60e92d1 | 1690 | .SH AUTHORS |
49da1240 | 1691 | |
d60e92d1 | 1692 | .B fio |
aa58d252 JA |
1693 | was written by Jens Axboe <jens.axboe@oracle.com>, |
1694 | now Jens Axboe <jaxboe@fusionio.com>. | |
d1429b5c AC |
1695 | .br |
1696 | This man page was written by Aaron Carroll <aaronc@cse.unsw.edu.au> based | |
d60e92d1 AC |
1697 | on documentation by Jens Axboe. |
1698 | .SH "REPORTING BUGS" | |
482900c9 | 1699 | Report bugs to the \fBfio\fR mailing list <fio@vger.kernel.org>. |
d1429b5c | 1700 | See \fBREADME\fR. |
d60e92d1 | 1701 | .SH "SEE ALSO" |
d1429b5c AC |
1702 | For further documentation see \fBHOWTO\fR and \fBREADME\fR. |
1703 | .br | |
1704 | Sample jobfiles are available in the \fBexamples\fR directory. | |
d60e92d1 | 1705 |