.B \-\-minimal
Print statistics in a terse, semicolon-delimited format.
.TP
+.B \-\-append-terse
+Print statistics in selected mode AND terse, semicolon-delimited format.
+.TP
.B \-\-version
Display version information and exit.
.TP
.B \-\-help
Display usage information and exit.
.TP
+.B \-\-cpuclock-test
+Perform test and validation of internal CPU clock
+.TP
+.BI \-\-crctest[\fR=\fPtest]
+Test the speed of the builtin checksumming functions. If no argument is given,
+all of them are tested. Or a comma separated list can be passed, in which
+case the given ones are tested.
+.TP
.BI \-\-cmdhelp \fR=\fPcommand
Print help information for \fIcommand\fR. May be `all' for all commands.
.TP
Turn on safety read-only checks, preventing any attempted write.
.TP
.BI \-\-section \fR=\fPsec
-Only run section \fIsec\fR from job file. Multiple of these options can be given, adding more sections to run.
+Only run section \fIsec\fR from job file. This option can be used multiple times to add more sections to run.
.TP
.BI \-\-alloc\-size \fR=\fPkb
Set the internal smalloc pool size to \fIkb\fP kilobytes.
may override any parameter set in global sections.
.SH "JOB PARAMETERS"
.SS Types
-Some parameters may take arguments of a specific type. The types used are:
+Some parameters may take arguments of a specific type.
+Anywhere a numeric value is required, an arithmetic expression may be used,
+provided it is surrounded by parentheses. Supported operators are:
+.RS
+.RS
+.TP
+.B addition (+)
+.TP
+.B subtraction (-)
+.TP
+.B multiplication (*)
+.TP
+.B division (/)
+.TP
+.B modulus (%)
+.TP
+.B exponentiation (^)
+.RE
+.RE
+.P
+For time values in expressions, units are microseconds by default. This is
+different than for time values not in expressions (not enclosed in
+parentheses). The types used are:
.TP
.I str
String: a sequence of alphanumeric characters.
SI integer: a whole number, possibly containing a suffix denoting the base unit
of the value. Accepted suffixes are `k', 'M', 'G', 'T', and 'P', denoting
kilo (1024), mega (1024^2), giga (1024^3), tera (1024^4), and peta (1024^5)
-respectively. The suffix is not case sensitive. If prefixed with '0x', the
-value is assumed to be base 16 (hexadecimal). A suffix may include a trailing 'b',
-for instance 'kb' is identical to 'k'. You can specify a base 10 value
-by using 'KiB', 'MiB', 'GiB', etc. This is useful for disk drives where
-values are often given in base 10 values. Specifying '30GiB' will get you
-30*1000^3 bytes.
+respectively. If prefixed with '0x', the value is assumed to be base 16
+(hexadecimal). A suffix may include a trailing 'b', for instance 'kb' is
+identical to 'k'. You can specify a base 10 value by using 'KiB', 'MiB','GiB',
+etc. This is useful for disk drives where values are often given in base 10
+values. Specifying '30GiB' will get you 30*1000^3 bytes.
+When specifying times the default suffix meaning changes, still denoting the
+base unit of the value, but accepted suffixes are 'D' (days), 'H' (hours), 'M'
+(minutes), 'S' Seconds, 'ms' (or msec) milli seconds, 'us' (or 'usec') micro
+seconds. Time values without a unit specify seconds.
+The suffixes are not case sensitive.
.TP
.I bool
Boolean: a true or false value. `0' denotes false, `1' denotes true.
.BI directory \fR=\fPstr
Prefix filenames with this directory. Used to place files in a location other
than `./'.
+You can specify a number of directories by separating the names with a ':'
+character. These directories will be assigned equally distributed to job clones
+creates with \fInumjobs\fR as long as they are using generated filenames.
+If specific \fIfilename(s)\fR are set fio will use the first listed directory,
+and thereby matching the \fIfilename\fR semantic which generates a file each
+clone if not specified, but let all clones use the same if set. See
+\fIfilename\fR for considerations regarding escaping certain characters on
+some platforms.
.TP
.BI filename \fR=\fPstr
.B fio
If the I/O engine is file-based, you can specify
a number of files by separating the names with a `:' character. `\-' is a
reserved name, meaning stdin or stdout, depending on the read/write direction
-set.
+set. On Windows, disk devices are accessed as \\.\PhysicalDrive0 for the first
+device, \\.\PhysicalDrive1 for the second etc. Note: Windows and FreeBSD
+prevent write access to areas of the disk containing in-use data
+(e.g. filesystems). If the wanted filename does need to include a colon, then
+escape that with a '\\' character. For instance, if the filename is
+"/dev/dsk/foo@3,0:c", then you would use filename="/dev/dsk/foo@3,0\\:c".
.TP
.BI filename_format \fR=\fPstr
If sharing multiple files between jobs, it is usually necessary to have
No locking. This is the default.
.TP
.B exclusive
-Only one thread or process may do IO at the time, excluding all others.
+Only one thread or process may do IO at a time, excluding all others.
.TP
.B readwrite
Read-write locking on the file. Many readers may access the file at the same
.BI unified_rw_reporting \fR=\fPbool
Fio normally reports statistics on a per data direction basis, meaning that
read, write, and trim are accounted and reported separately. If this option is
-set, the fio will sum the results and report them as "mixed" instead.
+set fio sums the results and reports them as "mixed" instead.
.TP
.BI randrepeat \fR=\fPbool
-Seed the random number generator in a predictable way so results are repeatable
-across runs. Default: true.
+Seed the random number generator used for random I/O patterns in a predictable
+way so the pattern is repeatable across runs. Default: true.
+.TP
+.BI allrandrepeat \fR=\fPbool
+Seed all random number generators in a predictable way so results are
+repeatable across runs. Default: false.
+.TP
+.BI randseed \fR=\fPint
+Seed the random number generators based on this seed value, to be able to
+control what sequence of output is being generated. If not set, the random
+sequence depends on the \fBrandrepeat\fR setting.
.TP
.BI use_os_rand \fR=\fPbool
-Fio can either use the random generator supplied by the OS to generator random
-offsets, or it can use it's own internal generator (based on Tausworthe).
+Fio can either use the random generator supplied by the OS to generate random
+offsets, or it can use its own internal generator (based on Tausworthe).
Default is to use the internal generator, which is often of better quality and
faster. Default: false.
.TP
.RE
.TP
.BI fadvise_hint \fR=\fPbool
-Use of \fBposix_fadvise\fR\|(2) to advise the kernel what I/O patterns
+Use \fBposix_fadvise\fR\|(2) to advise the kernel what I/O patterns
are likely to be issued. Default: true.
.TP
.BI size \fR=\fPint
divided between the available files for the job. If not set, fio will use the
full size of the given files or devices. If the files do not exist, size
must be given. It is also possible to give size as a percentage between 1 and
-100. If size=20% is given, fio will use 20% of the full size of the given files
-or devices.
+100. If size=20% is given, fio will use 20% of the full size of the given
+files or devices.
+.TP
+.BI io_limit \fR=\fPint
+Normally fio operates within the region set by \fBsize\fR, which means that
+the \fBsize\fR option sets both the region and size of IO to be performed.
+Sometimes that is not what you want. With this option, it is possible to
+define just the amount of IO that fio should do. For instance, if \fBsize\fR
+is set to 20G and \fBio_limit\fR is set to 5G, fio will perform IO within
+the first 20G but exit when 5G have been done.
.TP
.BI fill_device \fR=\fPbool "\fR,\fB fill_fs" \fR=\fPbool
Sets size to something really large and waits for ENOSPC (no space left on
that is given). If \fBfilesize\fR is not specified, each created file is the
same size.
.TP
+.BI file_append \fR=\fPbool
+Perform IO after the end of the file. Normally fio will operate within the
+size of a file. If this option is set, then fio will append to the file
+instead. This has identical behavior to setting \fRoffset\fP to the size
+of a file. This option is ignored on non-regular files.
+.TP
.BI blocksize \fR=\fPint[,int] "\fR,\fB bs" \fR=\fPint[,int]
Block size for I/O units. Default: 4k. Values for reads, writes, and trims
can be specified separately in the format \fIread\fR,\fIwrite\fR,\fItrim\fR
blocksize setting.
.TP
.B zero_buffers
-Initialise buffers with all zeros. Default: fill buffers with random data.
+Initialize buffers with all zeros. Default: fill buffers with random data.
+The resulting IO buffers will not be completely zeroed, unless
+\fPscramble_buffers\fR is also turned off.
.TP
.B refill_buffers
If this option is given, fio will refill the IO buffers on every submit. The
the remaining zeroed. With this set to some chunk size smaller than the block
size, fio can alternate random and zeroed data throughout the IO buffer.
.TP
+.BI buffer_pattern \fR=\fPstr
+If set, fio will fill the IO buffers with this pattern. If not set, the contents
+of IO buffers is defined by the other options related to buffer contents. The
+setting can be any pattern of bytes, and can be prefixed with 0x for hex
+values. It may also be a string, where the string must then be wrapped with
+"".
+.TP
+.BI dedupe_percentage \fR=\fPint
+If set, fio will generate this percentage of identical buffers when writing.
+These buffers will be naturally dedupable. The contents of the buffers depend
+on what other buffer compression settings have been set. It's possible to have
+the individual buffers either fully compressible, or not at all. This option
+only controls the distribution of unique buffers.
+.TP
.BI nrfiles \fR=\fPint
Number of files to use for this job. Default: 1.
.TP
Choose a file at random.
.TP
.B roundrobin
-Round robin over open files (default).
+Round robin over opened files (default).
.TP
.B sequential
Do each file in the set sequentially.
.RE
.P
-The number of I/Os to issue before switching a new file can be specified by
+The number of I/Os to issue before switching to a new file can be specified by
appending `:\fIint\fR' to the service type.
.RE
.TP
.B e4defrag
IO engine that does regular EXT4_IOC_MOVE_EXT ioctls to simulate defragment activity
request to DDIR_WRITE event
+.TP
+.B rbd
+IO engine supporting direct access to Ceph Rados Block Devices (RBD) via librbd
+without the need to use the kernel rbd driver. This ioengine defines engine specific
+options.
+.TP
+.B gfapi
+Using Glusterfs libgfapi sync interface to direct access to Glusterfs volumes without
+having to go through FUSE. This ioengine defines engine specific
+options.
+.TP
+.B gfapi_async
+Using Glusterfs libgfapi async interface to direct access to Glusterfs volumes without
+having to go through FUSE. This ioengine defines engine specific
+options.
+.TP
+.B libhdfs
+Read and write through Hadoop (HDFS). The \fBfilename\fR option is used to
+specify host,port of the hdfs name-node to connect. This engine interprets
+offsets a little differently. In HDFS, files once created cannot be modified.
+So random writes are not possible. To imitate this, libhdfs engine expects
+bunch of small files to be created over HDFS, and engine will randomly pick a
+file out of those files based on the offset generated by fio backend. (see the
+example job file to create such files, use rw=write option). Please note, you
+might want to set necessary environment variables to work with hdfs/libhdfs
+properly.
.RE
.P
.RE
.BI iodepth \fR=\fPint
Number of I/O units to keep in flight against the file. Note that increasing
iodepth beyond 1 will not affect synchronous ioengines (except for small
-degress when verify_async is in use). Even async engines my impose OS
+degress when verify_async is in use). Even async engines may impose OS
restrictions causing the desired depth not to be achieved. This may happen on
Linux when using libaio and not setting \fBdirect\fR=1, since buffered IO is
not async on that OS. Keep an eye on the IO depth distribution in the
.BI direct \fR=\fPbool
If true, use non-buffered I/O (usually O_DIRECT). Default: false.
.TP
+.BI atomic \fR=\fPbool
+If value is true, attempt to use atomic direct IO. Atomic writes are guaranteed
+to be stable once acknowledged by the operating system. Only Linux supports
+O_ATOMIC right now.
+.TP
.BI buffered \fR=\fPbool
If true, use buffered I/O. This is the opposite of the \fBdirect\fR parameter.
Default: true.
.TP
.BI offset_increment \fR=\fPint
If this is provided, then the real offset becomes the
-offset + offset_increment * thread_number, where the thread number is a counter
-that starts at 0 and is incremented for each job. This option is useful if
-there are several jobs which are intended to operate on a file in parallel in
-disjoint segments, with even spacing between the starting points.
+offset + offset_increment * thread_number, where the thread number is a
+counter that starts at 0 and is incremented for each sub-job (i.e. when
+numjobs option is specified). This option is useful if there are several jobs
+which are intended to operate on a file in parallel disjoint segments, with
+even spacing between the starting points.
.TP
.BI number_ios \fR=\fPint
Fio will normally perform IOs until it has exhausted the size of the region
set by \fBsize\fR, or if it exhaust the allocated time (or hits an error
condition). With this setting, the range/size can be set independently of
the number of IOs to perform. When fio reaches this number, it will exit
-normally and report status.
+normally and report status. Note that this does not extend the amount
+of IO that will be done, it will only stop fio if this condition is met
+before other end-of-job criteria.
.TP
.BI fsync \fR=\fPint
How many I/Os to perform before issuing an \fBfsync\fR\|(2) of dirty data. If
Average bandwidth for \fBrate\fR and \fBratemin\fR over this number of
milliseconds. Default: 1000ms.
.TP
+.BI latency_target \fR=\fPint
+If set, fio will attempt to find the max performance point that the given
+workload will run at while maintaining a latency below this target. The
+values is given in microseconds. See \fBlatency_window\fR and
+\fBlatency_percentile\fR.
+.TP
+.BI latency_window \fR=\fPint
+Used with \fBlatency_target\fR to specify the sample window that the job
+is run at varying queue depths to test the performance. The value is given
+in microseconds.
+.TP
+.BI latency_percentile \fR=\fPfloat
+The percentage of IOs that must fall within the criteria specified by
+\fBlatency_target\fR and \fBlatency_window\fR. If not set, this defaults
+to 100.0, meaning that all IOs must be equal or below to the value set
+by \fBlatency_target\fR.
+.TP
.BI max_latency \fR=\fPint
If set, fio will exit the job if it exceeds this maximum latency. It will exit
with an ETIME error.
.BI cpus_allowed \fR=\fPstr
Same as \fBcpumask\fR, but allows a comma-delimited list of CPU numbers.
.TP
+.BI cpus_allowed_policy \fR=\fPstr
+Set the policy of how fio distributes the CPUs specified by \fBcpus_allowed\fR
+or \fBcpumask\fR. Two policies are supported:
+.RS
+.RS
+.TP
+.B shared
+All jobs will share the CPU set specified.
+.TP
+.B split
+Each job will get a unique CPU from the CPU set.
+.RE
+.P
+\fBshared\fR is the default behaviour, if the option isn't specified. If
+\fBsplit\fR is specified, then fio will assign one cpu per job. If not enough
+CPUs are given for the jobs listed, then fio will roundrobin the CPUs in
+the set.
+.RE
+.P
+.TP
.BI numa_cpu_nodes \fR=\fPstr
Set this job running on specified NUMA nodes' CPUs. The arguments allow
comma delimited list of cpu numbers, A-B ranges, or 'all'.
allowed. For \fBbind\fR and \fBinterleave\fR, \fBnodelist\fR allows
comma delimited list of numbers, A-B ranges, or 'all'.
.TP
-.BI startdelay \fR=\fPint
-Delay start of job for the specified number of seconds.
+.BI startdelay \fR=\fPirange
+Delay start of job for the specified number of seconds. Supports all time
+suffixes to allow specification of hours, minutes, seconds and
+milliseconds - seconds are the default if a unit is ommited.
+Can be given as a range which causes each thread to choose randomly out of the
+range.
.TP
.BI runtime \fR=\fPint
Terminate processing after the specified number of seconds.
Specifies the number of iterations (runs of the same workload) of this job.
Default: 1.
.TP
+.BI verify_only \fR=\fPbool
+Do not perform the specified workload, only verify data still matches previous
+invocation of this workload. This option allows one to check data multiple
+times at a later date without overwriting it. This option makes sense only for
+workloads that write data, and does not support workloads with the
+\fBtime_based\fR option set.
+.TP
.BI do_verify \fR=\fPbool
Run the verify phase after a write phase. Only valid if \fBverify\fR is set.
Default: true.
.RS
.RS
.TP
-.B md5 crc16 crc32 crc32c crc32c-intel crc64 crc7 sha256 sha512 sha1
+.B md5 crc16 crc32 crc32c crc32c-intel crc64 crc7 sha256 sha512 sha1 xxhash
Store appropriate checksum in the header of each block. crc32c-intel is
hardware accelerated SSE4.2 driven, falls back to regular crc32c if
not supported by the system.
store data of the bandwidth of the jobs in their lifetime. The included
fio_generate_plots script uses gnuplot to turn these text files into nice
graphs. See \fBwrite_lat_log\fR for behaviour of given filename. For this
-option, the postfix is _bw.log.
+option, the postfix is _bw.x.log, where x is the index of the job (1..N,
+where N is the number of jobs)
.TP
.BI write_lat_log \fR=\fPstr
Same as \fBwrite_bw_log\fR, but writes I/O completion latencies. If no
-filename is given with this option, the default filename of "jobname_type.log"
-is used. Even if the filename is given, fio will still append the type of log.
+filename is given with this option, the default filename of
+"jobname_type.x.log" is used, where x is the index of the job (1..N, where
+N is the number of jobs). Even if the filename is given, fio will still
+append the type of log.
.TP
.BI write_iops_log \fR=\fPstr
Same as \fBwrite_bw_log\fR, but writes IOPS. If no filename is given with this
-option, the default filename of "jobname_type.log" is used. Even if the
-filename is given, fio will still append the type of log.
+option, the default filename of "jobname_type.x.log" is used, where x is the
+index of the job (1..N, where N is the number of jobs). Even if the filename
+is given, fio will still append the type of log.
.TP
.BI log_avg_msec \fR=\fPint
By default, fio will log an entry in the iops, latency, or bw log for every
over the specified period of time, reducing the resolution of the log.
Defaults to 0.
.TP
+.BI log_offset \fR=\fPbool
+If this is set, the iolog options will include the byte offset for the IO
+entry as well as the other data values.
+.TP
+.BI log_compression \fR=\fPint
+If this is set, fio will compress the IO logs as it goes, to keep the memory
+footprint lower. When a log reaches the specified size, that chunk is removed
+and compressed in the background. Given that IO logs are fairly highly
+compressible, this yields a nice memory savings for longer runs. The downside
+is that the compression will consume some background CPU cycles, so it may
+impact the run. This, however, is also true if the logging ends up consuming
+most of the system memory. So pick your poison. The IO logs are saved
+normally at the end of a run, by decompressing the chunks and storing them
+in the specified log file. This feature depends on the availability of zlib.
+.TP
+.BI log_store_compressed \fR=\fPbool
+If set, and \fBlog\fR_compression is also set, fio will store the log files in
+a compressed format. They can be decompressed with fio, using the
+\fB\-\-inflate-log\fR command line parameter. The files will be stored with a
+\fB\.fz\fR suffix.
+.TP
.BI disable_lat \fR=\fPbool
Disable measurements of total latency numbers. Useful only for cutting
back the number of calls to \fBgettimeofday\fR\|(2), as that does impact performance at
.BI ioscheduler \fR=\fPstr
Attempt to switch the device hosting the file to the specified I/O scheduler.
.TP
-.BI cpuload \fR=\fPint
-If the job is a CPU cycle-eater, attempt to use the specified percentage of
-CPU cycles.
-.TP
-.BI cpuchunks \fR=\fPint
-If the job is a CPU cycle-eater, split the load into cycles of the
-given time in milliseconds.
-.TP
.BI disk_util \fR=\fPbool
Generate disk utilization statistics if the platform supports it. Default: true.
.TP
.SS "Ioengine Parameters List"
Some parameters are only valid when a specific ioengine is in use. These are
used identically to normal parameters, with the caveat that when used on the
-command line, the must come after the ioengine that defines them is selected.
+command line, they must come after the ioengine.
.TP
.BI (cpu)cpuload \fR=\fPint
Attempt to use the specified percentage of CPU cycles.
.BI (cpu)cpuchunks \fR=\fPint
Split the load into cycles of the given time. In microseconds.
.TP
+.BI (cpu)exit_on_io_done \fR=\fPbool
+Detect when IO threads are done, then exit.
+.TP
.BI (libaio)userspace_reap
Normally, with the libaio engine in use, fio will use
the io_getevents system call to reap newly returned events.
.B tcp
Transmission control protocol
.TP
+.B tcpv6
+Transmission control protocol V6
+.TP
.B udp
User datagram protocol
.TP
+.B udpv6
+User datagram protocol V6
+.TP
.B unix
UNIX domain socket
.RE
.TP
.BI (net, pingpong) \fR=\fPbool
Normally a network writer will just continue writing data, and a network reader
-will just consume packages. If pingpong=1 is set, a writer will send its normal
+will just consume packets. If pingpong=1 is set, a writer will send its normal
payload to the reader, then wait for the reader to send the same payload back.
This allows fio to measure network latencies. The submission and completion
latencies then measure local time spent sending or receiving, and the
.BI 1:
allocate space immediately inside defragment event, and free right after event
.RE
+.TP
+.BI (rbd)rbdname \fR=\fPstr
+Specifies the name of the RBD.
+.TP
+.BI (rbd)pool \fR=\fPstr
+Specifies the name of the Ceph pool containing the RBD.
+.TP
+.BI (rbd)clientname \fR=\fPstr
+Specifies the username (without the 'client.' prefix) used to access the Ceph cluster.
.SH OUTPUT
While running, \fBfio\fR will display the status of the created jobs. For
example:
running, without terminating the job. To do that, send fio the \fBUSR1\fR
signal.
.SH TERSE OUTPUT
-If the \fB\-\-minimal\fR option is given, the results will be printed in a
-semicolon-delimited format suitable for scripted use - a job description
-(if provided) follows on a new line. Note that the first
+If the \fB\-\-minimal\fR / \fB\-\-append-terse\fR options are given, the
+results will be printed/appended in a semicolon-delimited format suitable for
+scripted use.
+A job description (if provided) follows on a new line. Note that the first
number in the line is the version number. If the output has to be changed
for some reason, this number will be incremented by 1 to signify that
change. The fields are:
projects / fio.git / blobdiff