| 1 | .TH fio 1 "September 2007" "User Manual" |
| 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 |
| 15 | .BI \-\-output \fR=\fPfilename |
| 16 | Write output to \fIfilename\fR. |
| 17 | .TP |
| 18 | .BI \-\-timeout \fR=\fPtimeout |
| 19 | Limit run time to \fItimeout\fR seconds. |
| 20 | .TP |
| 21 | .B \-\-latency\-log |
| 22 | Generate per-job latency logs. |
| 23 | .TP |
| 24 | .B \-\-bandwidth\-log |
| 25 | Generate per-job bandwidth logs. |
| 26 | .TP |
| 27 | .B \-\-minimal |
| 28 | Print statistics in a terse, semicolon\-delimited format. |
| 29 | .TP |
| 30 | .BI \-\-showcmd \fR=\fPjobfile |
| 31 | Convert \fIjobfile\fR to a set of command-line options. |
| 32 | .TP |
| 33 | .B \-\-readonly |
| 34 | Enable read-only safety checks. |
| 35 | .TP |
| 36 | .BI \-\-eta \fR=\fPwhen |
| 37 | Specifies when real-time ETA estimate should be printed. \fIwhen\fR may |
| 38 | be one of `always', `never' or `auto'. |
| 39 | .TP |
| 40 | .BI \-\-cmdhelp \fR=\fPcommand |
| 41 | Print help information for \fIcommand\fR. May be `all' for all commands. |
| 42 | .TP |
| 43 | .B \-\-help |
| 44 | Display usage information and exit. |
| 45 | .TP |
| 46 | .B \-\-version |
| 47 | Display version information and exit. |
| 48 | .SH "JOB FILE FORMAT" |
| 49 | Job files are in `ini' format. They consist of one or more |
| 50 | job definitions, which begin with a job name in square brackets and |
| 51 | extend to the next job name. The job name can be any ASCII string |
| 52 | except `global', which has a special meaning. Following the job name is |
| 53 | a sequence of zero or more parameters, one per line, that define the |
| 54 | behavior of the job. Any line starting with a `;' or `#' character is |
| 55 | considered a comment and ignored. See section EXAMPLES for sample |
| 56 | job files. |
| 57 | .SS "Global Section" |
| 58 | The global section contains default parameters for jobs specified in the |
| 59 | job file. A job is only affected by global sections residing above it, |
| 60 | and there may be any number of global sections. Specific job definitions |
| 61 | may override any parameter set in global sections. |
| 62 | .SH "JOB PARAMETERS" |
| 63 | .SS Types |
| 64 | Some parameters may take arguments of a specific type. The types used are: |
| 65 | .TP |
| 66 | .I str |
| 67 | String: a sequence of alphanumeric characters. |
| 68 | .TP |
| 69 | .I int |
| 70 | Integer: a whole number, possibly negative. If prefixed with `0x', the value |
| 71 | is assumed to be base 16 (hexadecimal). |
| 72 | .TP |
| 73 | .I siint |
| 74 | SI integer: a whole number, possibly containing a suffix denoting the base unit |
| 75 | of the value. Accepted suffixes are `k', 'M' and 'G', denoting kilo (1024), |
| 76 | mega (1024*1024) and giga (1024*1024*1024) respectively. |
| 77 | .TP |
| 78 | .I bool |
| 79 | Boolean: a true or false value. `0' denotes false, `1' denotes true. |
| 80 | .TP |
| 81 | .I irange |
| 82 | Integer range: a range of integers specified in the format |
| 83 | \fIlower\fR:\fIupper\fR or \fIlower\fR-\fIupper\fR. \fIlower\fR and \fIupper\fR |
| 84 | may contain a suffix as described above. If an option allows two sets of ranges, |
| 85 | they are separated with a `,' or `/' character. For example: `8-8k/8M-4G'. |
| 86 | .SS "Parameter List" |
| 87 | .TP |
| 88 | .BI name \fR=\fPstr |
| 89 | May be used to override the job name. On the command line, this paramter |
| 90 | has the special purpose of signalling the start of a new job. |
| 91 | .TP |
| 92 | .BI description \fR=\fPstr |
| 93 | Human-readable description of the job. It is printed when the job is run, but |
| 94 | otherwise has no special purpose. |
| 95 | .TP |
| 96 | .BI directory \fR=\fPstr |
| 97 | Prefix filenames with this directory. Used to place files in a location other |
| 98 | than `./'. |
| 99 | .TP |
| 100 | .BI filename \fR=\fPstr |
| 101 | .B fio |
| 102 | normally makes up a file name based on the job name, thread number, and file |
| 103 | number. If you want to share files between threads in a job or several jobs, specify |
| 104 | a \fIfilename\fR for each of them to override the default. If the I/O engine used is |
| 105 | `net', \fIfilename\fR is the host and port to connect to in the format |
| 106 | \fIhost\fR/\fIport\fR. If the I/O engine is file-based, you can specify a number of |
| 107 | files by separating the names with a `:' character. `-' is a reserved name, meaning |
| 108 | stdin or stdout, depending on the read/write direction set. |
| 109 | .TP |
| 110 | .BI opendir \fR=\fPstr |
| 111 | Recursively open any files below directory \fIstr\fR. |
| 112 | .TP |
| 113 | .BI readwrite \fR=\fPstr "\fR,\fP rw" \fR=\fPstr |
| 114 | Type of I/O pattern. Accepted values are: |
| 115 | .RS |
| 116 | .RS |
| 117 | .TP |
| 118 | .B read |
| 119 | Sequential reads |
| 120 | .TP |
| 121 | .B write |
| 122 | Sequential writes |
| 123 | .TP |
| 124 | .B randread |
| 125 | Random reads |
| 126 | .TP |
| 127 | .B randwrite |
| 128 | Random writes |
| 129 | .TP |
| 130 | .B rw |
| 131 | Mixed sequential reads and writes |
| 132 | .TP |
| 133 | .B randrw |
| 134 | Mixed random reads and writes |
| 135 | .RE |
| 136 | .P |
| 137 | For mixed I/O, the default split is 50/50. For random I/O, the number of I/Os to |
| 138 | perform before getting a new offset can be specified by appending `:\fIint\fR' to |
| 139 | the pattern type. The default is 1. |
| 140 | .RE |
| 141 | .TP |
| 142 | .BI randrepeat \fR=\fPbool |
| 143 | Seed the random number generator in a predictable way so results are repeatable |
| 144 | across runs. |
| 145 | .TP |
| 146 | .BI fadvise_hint \fR=\fPbool |
| 147 | Disable use of \fIposix_fadvise\fR\|(2) to advise the kernel what I/O patters are |
| 148 | likely to be issued. Default: true. |
| 149 | .TP |
| 150 | .BI size \fR=\fPsiint |
| 151 | Total size of I/O for this job. \fBfio\fR will run until this many bytes have |
| 152 | been transfered, unless limited by other options (\fBruntime\fR, for instance). |
| 153 | Unless \fBnr_files\fR and \fBfilesize\fR options are given, this amount will be |
| 154 | divided between the available files for the job. |
| 155 | .TP |
| 156 | .BI filesize \fR=\fPirange |
| 157 | Individual file sizes. May be a range, in which case \fBfio\fR will select sizes |
| 158 | for files at random within the given range, limited to \fBsize\fR in total (if that |
| 159 | is given). If \fBfilesize\fR is not specified, each created file is the same size. |
| 160 | .TP |
| 161 | .BI blocksize \fR=\fPsiint "\fR,\fB bs" \fR=\fPsiint |
| 162 | Block size for I/O units. Default: 4k. Values for reads and writes can be |
| 163 | specified seperately in the format \fIread\fR,\fIwrite\fR, either of |
| 164 | which may be empty to leave that value at its default. |
| 165 | .TP |
| 166 | .BI blocksize_range \fR=\fPirange "\fR,\fB bsrange" \fR=\fPirange |
| 167 | Specify a range of I/O block sizes. The issued I/O unit will always be a multiple |
| 168 | of the minimum size, unless \fBblocksize_unaligned\fR is set. Applied to both reads |
| 169 | and writes, but can be specified seperately (see \fBblocksize\fR). |
| 170 | .TP |
| 171 | .B blocksize_unaligned\fR,\fP bs_unaligned |
| 172 | If set, any size in \fBblocksize_range\fR may be used. This typically won't work |
| 173 | with direct I/O, as that normally requires sector alignment. |
| 174 | .TP |
| 175 | .B zero_buffers |
| 176 | Initialise buffers with all zeros. Default: fill buffers with random data. |
| 177 | .TP |
| 178 | .BI nrfiles \fR=\fPint |
| 179 | Number of files to use for this job. Default: 1. |
| 180 | .TP |
| 181 | .BI openfiles \fR=\fPint |
| 182 | Number of files to keep open at the same time. Default: \fBnrfiles\fR. |
| 183 | .TP |
| 184 | .BI file_service_type \fR=\fPstr |
| 185 | Defines how files to service are selected. The following types are defined: |
| 186 | .RS |
| 187 | .RS |
| 188 | .TP |
| 189 | .B random |
| 190 | Choose a file at random |
| 191 | .TP |
| 192 | .B roundrobin |
| 193 | Round robin over open files (default). |
| 194 | .RE |
| 195 | .P |
| 196 | The number of I/Os to issue before switching a new file can be specified by |
| 197 | appending `:\fIint\fR' to the service type. |
| 198 | .RE |
| 199 | .TP |
| 200 | .BI ioengine \fR=\fPstr |
| 201 | Defines how the job issues I/O. The following types are defined: |
| 202 | .RS |
| 203 | .RS |
| 204 | .TP |
| 205 | .B sync |
| 206 | Basic \fIread\fR\|(2) or \fIwrite\fR\|(2) I/O. \fIfseek\fR\|(2) is used to |
| 207 | position the I/O location. |
| 208 | .TP |
| 209 | .B libaio |
| 210 | Linux native asynchronous I/O. |
| 211 | .TP |
| 212 | .B posixaio |
| 213 | glibc POSIX asynchronous I/O using \fIaio_read\fR\|(3) and \fIaio_write\fR\|(3). |
| 214 | .TP |
| 215 | .B mmap |
| 216 | File is memory mapped with \fImmap\fR\|(2) and data coped using \fImemcpy\fR\|(3). |
| 217 | .TP |
| 218 | .B splice |
| 219 | \fIsplice\fR\|(2) is used to transfer the data and \fIvmsplice\fR\|(2) to transfer |
| 220 | data from user-space to the kernel. |
| 221 | .TP |
| 222 | .B syslet-rw |
| 223 | Use the syslet system calls to make regular read/write asynchronous. |
| 224 | .TP |
| 225 | .B sg |
| 226 | SCSI generic sg v3 I/O. May be either synchronous using the SG_IO ioctl, or if |
| 227 | the target is an sg character device, we use \fIread\fR\|(2) and \fIwrite\fR\|(2) |
| 228 | for asynchronous I/O. |
| 229 | .TP |
| 230 | .B null |
| 231 | Doesn't transfer any data, just pretends to. Mainly used to exercise \fBfio\fR |
| 232 | itself and for debugging and testing purposes. |
| 233 | .TP |
| 234 | .B net |
| 235 | Transfer over the network. \fBfilename\fR must be set appropriately to |
| 236 | `\fIhost\fR/\fIport\fR' regardless of data direction. If receiving, only the |
| 237 | \fIport\fR argument is used. |
| 238 | .TP |
| 239 | .B netsplice |
| 240 | Like \fBnet\fR, but uses \fIsplice\fR\|(2) and \fIvmsplice\fR\|(2) to map data |
| 241 | and send/receive. |
| 242 | .TP |
| 243 | .B cpu |
| 244 | Doesn't transfer any data, but burns CPU cycles according to \fBcpuload\fR and |
| 245 | \fBcpucycles\fR parameters. |
| 246 | .TP |
| 247 | .B guasi |
| 248 | The GUASI I/O engine is the Generic Userspace Asynchronous Syscall Interface |
| 249 | approach to asycnronous I/O. |
| 250 | |
| 251 | See <http://www.xmailserver.org/guasi-lib.html>. |
| 252 | .TP |
| 253 | .B external |
| 254 | Loads an external I/O engine object file. Append the engine filename as |
| 255 | `:\fIenginepath\fR'. |
| 256 | .RE |
| 257 | .RE |
| 258 | .TP |
| 259 | .BI iodepth \fR=\fPint |
| 260 | Number of I/O units to keep in flight against the file. Default: 1. |
| 261 | .TP |
| 262 | .BI iodepth_batch \fR=\fPint |
| 263 | Number of I/Os to submit at once. Default: \fBiodepth\fR. |
| 264 | .TP |
| 265 | .BI iodepth_low \fR=\fPint |
| 266 | Low watermark indicating when to start filling the queue again. Default: |
| 267 | \fBiodepth\fR. |
| 268 | .TP |
| 269 | .BI direct \fR=\fPbool |
| 270 | If true, use non-buffered I/O (usually O_DIRECT). Default: false. |
| 271 | .TP |
| 272 | .BI buffered \fR=\fPbool |
| 273 | If true, use buffered I/O. This is the opposite of the \fBdirect\fR parameter. |
| 274 | Default: true. |
| 275 | .TP |
| 276 | .BI offset \fR=\fPsiint |
| 277 | Offset in the file to start I/O. Data before the offset will not be touched. |
| 278 | .TP |
| 279 | .BI fsync \fR=\fPint |
| 280 | How many I/Os to perform before issuing an \fBfsync\fR\|(2) of dirty data. If 0, don't |
| 281 | sync. Default: 0. |
| 282 | .TP |
| 283 | .BI overwrite \fR=\fPbool |
| 284 | If writing, setup the file first and do overwrites. |
| 285 | .TP |
| 286 | .BI end_fsync \fR=\fPbool |
| 287 | If true, sync file contents when job exits. |
| 288 | .TP |
| 289 | .BI fsync_on_close \fR=\fPbool |
| 290 | If true, sync file contents on close. This differs from \fBend_fsync\fR in that |
| 291 | it will happen on every close, not just at the end of the job. |
| 292 | .TP |
| 293 | .BI rwmixcycle \fR=\fPint |
| 294 | How many milliseconds before switching between reads and writes for a mixed |
| 295 | workload. Default: 500ms. |
| 296 | .TP |
| 297 | .BI rwmixread \fR=\fPint |
| 298 | Percentage of a mixed workload that should be reads. Default: 50. |
| 299 | .TP |
| 300 | .BI rwmixwrite \fR=\fPint |
| 301 | Percentage of a mixed workload that would be writes. If \fBrwmixread\fR and |
| 302 | \fBwrmixwrite\fR are given and do not sum to 100%, the latter of the two |
| 303 | overrides the first. |
| 304 | .TP |
| 305 | .B norandommap |
| 306 | Normally \fBfio\fR will cover every block of the file when doing random I/O. If |
| 307 | this parameter is given, a new offset will be chosen without looking at past |
| 308 | I/O history. This parameter is mutually exclusive with \fBverify\fR. |
| 309 | .TP |
| 310 | .BI nice \fR=\fPint |
| 311 | Run job with given nice value. See \fInice\fR\|(2). |
| 312 | .TP |
| 313 | .BI prio \fR=\fPint |
| 314 | Set I/O priority value of this job between 0 (highest) and 7 (lowest). See |
| 315 | \fIionice\fR\|(1). |
| 316 | .TP |
| 317 | .BI prioclass \fR=\fPint |
| 318 | Set I/O priority class. See \fIionice\fR\|(1). |
| 319 | .TP |
| 320 | .BI thinktime \fR=\fPint |
| 321 | Stall job for given number of microseconds between issuing I/Os. |
| 322 | .TP |
| 323 | .BI thinktime_spin \fR=\fPint |
| 324 | Pretend to spend CPU time for given number of microseconds, sleeping the rest |
| 325 | of the time specified by \fBthinktime\fR. Only valid if \fBthinktime\fR is set. |
| 326 | .TP |
| 327 | .BI thinktime_blocks \fR=\fPint |
| 328 | Number of blocks to issue before waiting \fBthinktime\fR microseconds. |
| 329 | Default: 1. |
| 330 | .TP |
| 331 | .BI rate \fR=\fPint |
| 332 | Cap bandwidth used by this job to this number of KiB/s. |
| 333 | .TP |
| 334 | .BI ratemin \fR=\fPint |
| 335 | Tell \fBfio\fR to do whatever it can to maintain at least the given bandwidth. |
| 336 | Failing to meet this requirement will cause the job to exit. |
| 337 | .TP |
| 338 | .BI rate_iops \fR=\fPint |
| 339 | Cap the bandwidth to this number of IOPS. If \fBblocksize\fR is a range, the |
| 340 | smallest block size is used as the metric. |
| 341 | .TP |
| 342 | .BI rate_iops_min \fR=\fPint |
| 343 | If this rate of I/O is not met, the job will exit. |
| 344 | .TP |
| 345 | .BI ratecycle \fR=\fPint |
| 346 | Average bandwidth for \fBrate\fR and \fBratemin\fR over this number of |
| 347 | milliseconds. Default: 1000ms. |
| 348 | .TP |
| 349 | .BI cpumask \fR=\fPint |
| 350 | Set CPU affinity for this job. \fIint\fR is a bitmask of allowed CPUs the job |
| 351 | may run on. See \fBsched_setaffinity\fR\|(2). |
| 352 | .TP |
| 353 | .BI cpus_allowed \fR=\fPstr |
| 354 | Same as \fBcpumask\fR, but allows a comma-delimited list of CPU numbers. |
| 355 | .TP |
| 356 | .BI startdelay \fR=\fPint |
| 357 | Delay start of job for the specified number of seconds. |
| 358 | .TP |
| 359 | .BI runtime \fR=\fPint |
| 360 | Terminate processing after the specified number of seconds. |
| 361 | .TP |
| 362 | .B time_based |
| 363 | If given, run for the specified \fBruntime\fR duration even if the files are |
| 364 | completely read or written. The same workload will be repeated as many times |
| 365 | as \fBruntime\fR allows. |
| 366 | .TP |
| 367 | .BI invalidate \fR=\fPbool |
| 368 | Invalidate buffer-cache for the file prior to starting I/O. Default: true. |
| 369 | .TP |
| 370 | .BI sync \fR=\fPbool |
| 371 | Use synchronous I/O for buffered writes. For the majority of I/O engines, |
| 372 | this means using O_SYNC. |
| 373 | .TP |
| 374 | .BI iomem \fR=\fPstr "\fR,\fP mem" \fR=\fPstr |
| 375 | Allocation method for I/O unit buffer. Allowed values are: |
| 376 | .RS |
| 377 | .RS |
| 378 | .TP |
| 379 | .B malloc |
| 380 | Allocate memory with \fImalloc\fR\|(3). |
| 381 | .TP |
| 382 | .B shm |
| 383 | Use shared memory buffers allocated through \fIshmget\fR\|(2). |
| 384 | .TP |
| 385 | .B shmhuge |
| 386 | Same as \fBshm\fR, but use huge pages as backing. |
| 387 | .TP |
| 388 | .B mmap |
| 389 | Use \fImmap\fR\|(2) for allocation. Uses anonymous memory unless a filename |
| 390 | is given after the option in the format `:\fIfile\fR'. |
| 391 | .TP |
| 392 | .B mmaphuge |
| 393 | Same as \fBmmap\fR, but use huge files as backing. |
| 394 | .RE |
| 395 | .P |
| 396 | The amount of memory allocated is the maximum allowed \fBblocksize\fR for the |
| 397 | job multiplied by \fBiodepth\fR. For \fBshmhuge\fR or \fBmmaphuge\fR to work, |
| 398 | the system must have free huge pages allocated. \fBmmaphuge\fR also needs to |
| 399 | have hugetlbfs mounted, and \fIfile\fR must point there. |
| 400 | .RE |
| 401 | .TP |
| 402 | .BI hugepage-size \fR=\fPsiint |
| 403 | Defines the size of a huge page. Must be at least equal to the system setting. |
| 404 | Should be a multiple of 1MiB. Default: 4MiB. |
| 405 | .TP |
| 406 | .B exitall |
| 407 | Terminate all jobs when one finishes. Default: wait for each job to finish. |
| 408 | .TP |
| 409 | .BI bwavgtime \fR=\fPint |
| 410 | Average bandwidth calculations over the given time in milliseconds. Default: |
| 411 | 500ms. |
| 412 | .TP |
| 413 | .BI create_serialize \fR=\fPbool |
| 414 | If true, serialize file creation for the jobs. |
| 415 | .TP |
| 416 | .BI create_fsync \fR=\fPbool |
| 417 | \fIfsync\fR\|(2) data file after creation. Default: true. |
| 418 | .TP |
| 419 | .BI unlink \fR=\fPbool |
| 420 | Unlink job files when done. Default: false. |
| 421 | .TP |
| 422 | .BI loops \fR=\fPint |
| 423 | Specifies the number of iterations (runs of the same workload) of this job. |
| 424 | Default: 1. |
| 425 | .TP |
| 426 | .BI do_verify \fR=\fPbool |
| 427 | Run the verify phase after a write phase. Only valid if \fBverify\fR is set. |
| 428 | Default: true. |
| 429 | .TP |
| 430 | .BI verify \fR=\fPstr |
| 431 | Method of verifying file contents after each iteration of the job. Allowed |
| 432 | values are: |
| 433 | .RS |
| 434 | .RS |
| 435 | .TP |
| 436 | .B md5 crc16 crc32 crc64 crc7 sha256 sha512 |
| 437 | Store appropriate checksum in the header of each block. |
| 438 | .TP |
| 439 | .B meta |
| 440 | Write extra information about each I/O (timestamp, block number, etc.). The |
| 441 | block number is verified. |
| 442 | .TP |
| 443 | .B pattern |
| 444 | Fill I/O buffers with a specific pattern that is used to verify. The pattern is |
| 445 | specified by appending `:\fIint\fR' to the parameter. \fIint\fR cannot be larger |
| 446 | than 32-bits. |
| 447 | .TP |
| 448 | .B null |
| 449 | Pretend to verify. Used for testing internals. |
| 450 | .RE |
| 451 | .RE |
| 452 | .TP |
| 453 | .BI verify_sort \fR=\fPbool |
| 454 | If true, written verify blocks are sorted if \fBfio\fR deems it to be faster to |
| 455 | read them back in a sorted manner. Default: true. |
| 456 | .TP |
| 457 | .BI verify_offset \fR=\fPsiint |
| 458 | Swap the verification header with data somewhere else in the block before |
| 459 | writing. It it swapped back before verifying. |
| 460 | .TP |
| 461 | .BI verify_interval \fR=\fPsiint |
| 462 | Write the verification header for this number of bytes, which should divide |
| 463 | \fBblocksize\fR. Default: \fBblocksize\fR. |
| 464 | .TP |
| 465 | .BI verify_fatal \fR=\fPbool |
| 466 | If true, exit the job on the first observed verification failure. Default: |
| 467 | false. |
| 468 | .TP |
| 469 | .B stonewall |
| 470 | Wait for precedding jobs in the job file to exit before starting this one. |
| 471 | \fBstonewall\fR implies \fBnew_group\fR. |
| 472 | .TP |
| 473 | .B new_group |
| 474 | Start a new reporting group. If not given, all jobs in a file will be part |
| 475 | of the same reporting group, unless separated by a stonewall. |
| 476 | .TP |
| 477 | .BI numjobs \fR=\fPint |
| 478 | Number of clones (processes/threads performing the same workload) of this job. |
| 479 | Default: 1. |
| 480 | .TP |
| 481 | .B group_reporting |
| 482 | If set, display per-group reports instead of per-job when \fBnumjobs\fR is |
| 483 | specified. |
| 484 | .TP |
| 485 | .B thread |
| 486 | Use threads created with \fBpthread_create\fR\|(3) instead of processes created |
| 487 | with \fBfork\fR\|(2). |
| 488 | .TP |
| 489 | .BI zonesize \fR=\fPsiint |
| 490 | Divide file into zones of the specified size in bytes. See \fBzoneskip\fR. |
| 491 | .TP |
| 492 | .BI zoneskip \fR=\fPsiint |
| 493 | Skip the specified number of bytes when \fBzonesize\fR bytes of data has been |
| 494 | read. |
| 495 | .TP |
| 496 | .BI write_iolog \fR=\fPstr |
| 497 | Write the issued I/O patterns to the specified file. |
| 498 | .TP |
| 499 | .BI read_iolog \fR=\fPstr |
| 500 | Replay the I/O patterns contained in the specified file generated by |
| 501 | \fBwrite_iolog\fR, or may be a \fBblktrace\fR binary file. |
| 502 | .TP |
| 503 | .B write_bw_log |
| 504 | If given, write bandwidth logs of the jobs in this file. |
| 505 | .TP |
| 506 | .B write_lat_log |
| 507 | Same as \fBwrite_bw_log\fR, but writes I/O completion latencies. |
| 508 | .TP |
| 509 | .BI lockmem \fR=\fPsiint |
| 510 | Pin the specified amount of memory with \fBmlock\fR\|(2). Can be used to |
| 511 | simulate a smaller amount of memory. |
| 512 | .TP |
| 513 | .BI exec_prerun \fR=\fPstr |
| 514 | Before running the job, execute the specified command with \fBsystem\fR\|(3). |
| 515 | .TP |
| 516 | .BI exec_postrun \fR=\fPstr |
| 517 | Same as \fBexec_prerun\fR, but the command is executed after the job completes. |
| 518 | .TP |
| 519 | .BI ioscheduler \fR=\fPstr |
| 520 | Attempt to switch the device hosting the file to the specified I/O scheduler. |
| 521 | .TP |
| 522 | .BI cpuload \fR=\fPint |
| 523 | If the job is a CPU cycle-eater, attempt to use the specified percentage of |
| 524 | CPU cycles. |
| 525 | .TP |
| 526 | .BI cpuchunks \fR=\fPint |
| 527 | If the job is a CPU cycle-eater, split the load into cycles of the |
| 528 | given time in milliseconds. |
| 529 | .TP |
| 530 | .BI disk_util \fR=\fPbool |
| 531 | Generate disk utilization statistics if the platform supports it. Default: true. |
| 532 | .SH OUTPUT |
| 533 | While running, \fBfio\fR will display the status of the created jobs. For example: |
| 534 | .RS |
| 535 | Threads: 1: [_r] [24.8% done] [ 13509/ 8334 kb/s] [eta 00h:01m:31s] |
| 536 | .RE |
| 537 | .P |
| 538 | The characters in the first set of brackets denote the current status of each threads. |
| 539 | The possible values are: |
| 540 | .RS |
| 541 | .RS |
| 542 | .TP |
| 543 | .B P |
| 544 | Setup but not started. |
| 545 | .TP |
| 546 | .B C |
| 547 | Thread created. |
| 548 | .TP |
| 549 | .B I |
| 550 | Initialized, waiting. |
| 551 | .TP |
| 552 | .B R |
| 553 | Running, doing sequential reads. |
| 554 | .TP |
| 555 | .B r |
| 556 | Running, doing random reads. |
| 557 | .TP |
| 558 | .B W |
| 559 | Running, doing sequential writes. |
| 560 | .TP |
| 561 | .B w |
| 562 | Running, doing random writes. |
| 563 | .TP |
| 564 | .B M |
| 565 | Running, doing mixed sequential reads/writes. |
| 566 | .TP |
| 567 | .B m |
| 568 | Running, doing mixed random reads/writes. |
| 569 | .TP |
| 570 | .B F |
| 571 | Running, currently waiting for \fBfsync\fR\|(2). |
| 572 | .TP |
| 573 | .B V |
| 574 | Running, verifying written data. |
| 575 | .TP |
| 576 | .B E |
| 577 | Exited, not reaped by main thread. |
| 578 | .TP |
| 579 | .B \- |
| 580 | Exited, thread reaped. |
| 581 | .RE |
| 582 | .RE |
| 583 | .P |
| 584 | The second set of brackets shows the estimated completion percentage of |
| 585 | the current group. The third set shows the read and write I/O rate, |
| 586 | respectively. Finally, the estimated run time of the job is displayed. |
| 587 | .P |
| 588 | When \fBfio\fR completes (or is interrupted by Ctrl-C), it will show data |
| 589 | for each thread, each group of threads, and each disk, in that order. |
| 590 | .P |
| 591 | Per-thread statistics first show the threads client number, group-id, and |
| 592 | error code. The remaining figures are as follows: |
| 593 | .RS |
| 594 | .RS |
| 595 | .TP |
| 596 | .B io |
| 597 | Number of megabytes of I/O performed. |
| 598 | .TP |
| 599 | .B bw |
| 600 | Average data rate (bandwidth). |
| 601 | .TP |
| 602 | .B runt |
| 603 | Threads run time. |
| 604 | .TP |
| 605 | .B slat |
| 606 | Submission latency minimum, maximum, average and standard deviation. This is |
| 607 | the time it took to submit the I/O. |
| 608 | .TP |
| 609 | .B clat |
| 610 | Completion latency minimum, maximum, average and standard deviation. This |
| 611 | is the time between submission and completion. |
| 612 | .TP |
| 613 | .B bw |
| 614 | Bandwidth minimum, maximum, percentage of aggregate bandwidth received, average |
| 615 | and standard deviation. |
| 616 | .TP |
| 617 | .B cpu |
| 618 | CPU usage statistics. Includes user and system time, number of context switches |
| 619 | this thread went through and number of major and minor page faults. |
| 620 | .TP |
| 621 | .B IO depths |
| 622 | Distribution of I/O depths. Each depth includes everything less than (or equal) |
| 623 | to it, but greater than the previous depth. |
| 624 | .TP |
| 625 | .B IO issued |
| 626 | Number of read/write requests issued, and number of short read/write requests. |
| 627 | .TP |
| 628 | .B IO latencies |
| 629 | Distribution of I/O completion latencies. The numbers follow the same pattern |
| 630 | as \fBIO depths\fR. |
| 631 | .RE |
| 632 | .RE |
| 633 | .P |
| 634 | The group statistics show: |
| 635 | .RS |
| 636 | .RS |
| 637 | .TP |
| 638 | .B io |
| 639 | Number of megabytes I/O performed. |
| 640 | .TP |
| 641 | .B aggrb |
| 642 | Aggregate bandwidth of threads in the group. |
| 643 | .TP |
| 644 | .B minb |
| 645 | Minimum average bandwidth a thread saw. |
| 646 | .TP |
| 647 | .B maxb |
| 648 | Maximum average bandwidth a thread saw. |
| 649 | .TP |
| 650 | .B mint |
| 651 | Smallest runtime of threads in the group. |
| 652 | .TP |
| 653 | .B maxt |
| 654 | Longest runtime of threads in the group. |
| 655 | .RE |
| 656 | .RE |
| 657 | .P |
| 658 | Finally, disk statistics are printed with reads first: |
| 659 | .RS |
| 660 | .RS |
| 661 | .TP |
| 662 | .B ios |
| 663 | Number of I/Os performed by all groups. |
| 664 | .TP |
| 665 | .B merge |
| 666 | Number of merges in the I/O scheduler. |
| 667 | .TP |
| 668 | .B ticks |
| 669 | Number of ticks we kept the disk busy. |
| 670 | .TP |
| 671 | .B io_queue |
| 672 | Total time spent in the disk queue. |
| 673 | .TP |
| 674 | .B util |
| 675 | Disk utilization. |
| 676 | .RE |
| 677 | .RE |
| 678 | .SH TERSE OUTPUT |
| 679 | If the \fB\-\-minimal\fR option is given, the results will be printed in a |
| 680 | semicolon-delimited format suitable for scripted use. The fields are: |
| 681 | .P |
| 682 | .RS |
| 683 | .B jobname, groupid, error |
| 684 | .P |
| 685 | Read status: |
| 686 | .RS |
| 687 | .B KiB I/O, bandwidth \fR(KiB/s)\fP, runtime \fR(ms)\fP |
| 688 | .P |
| 689 | Submission latency: |
| 690 | .RS |
| 691 | .B min, max, mean, standard deviation |
| 692 | .RE |
| 693 | Completion latency: |
| 694 | .RS |
| 695 | .B min, max, mean, standard deviation |
| 696 | .RE |
| 697 | Bandwidth: |
| 698 | .RS |
| 699 | .B min, max, aggregate percentage of total, mean, standard deviation |
| 700 | .RE |
| 701 | .RE |
| 702 | .P |
| 703 | Write status: |
| 704 | .RS |
| 705 | .B KiB I/O, bandwidth \fR(KiB/s)\fP, runtime \fR(ms)\fP |
| 706 | .P |
| 707 | Submission latency: |
| 708 | .RS |
| 709 | .B min, max, mean, standard deviation |
| 710 | .RE |
| 711 | Completion latency: |
| 712 | .RS |
| 713 | .B min, max, mean, standard deviation |
| 714 | .RE |
| 715 | Bandwidth: |
| 716 | .RS |
| 717 | .B min, max, aggregate percentage of total, mean, standard deviation |
| 718 | .RE |
| 719 | .RE |
| 720 | .P |
| 721 | CPU usage; |
| 722 | .RS |
| 723 | .B user, system, context switches |
| 724 | .RE |
| 725 | .P |
| 726 | IO depth distribution: |
| 727 | .RS |
| 728 | .B <=1, 2, 4, 8, 16, 32, >=64 |
| 729 | .RE |
| 730 | .P |
| 731 | IO latency distribution (ms): |
| 732 | .RS |
| 733 | .B <=2, 4, 10, 20, 50, 100, 250, 500, 750, 1000, >=2000 |
| 734 | .RE |
| 735 | .P |
| 736 | .B text description |
| 737 | .RE |
| 738 | .SH AUTHORS |
| 739 | .B fio |
| 740 | was written by Jens Axboe <jens.axboe@oracle.com>. |
| 741 | This man page was |
| 742 | written by Aaron Carroll <aaronc@cse.unsw.edu.au> based |
| 743 | on documentation by Jens Axboe. |
| 744 | .SH "REPORTING BUGS" |
| 745 | Report bugs to the \fBfio\fR mailing list <fio-devel@kernel.dk>. See \fBREADME\fR. |
| 746 | .SH "SEE ALSO" |
| 747 | Further documentation is available in \fBfio\fR's \fBHOWTO\fR and \fBREADME\fR. |
| 748 | Sample jobfiles are available in \fBfio\fR's \fBexamples/\fR directory. |
| 749 | |