-.TH fio 1 "May 2017" "User Manual"
+.TH fio 1 "July 2017" "User Manual"
.SH NAME
fio \- flexible I/O tester
.SH SYNOPSIS
.TP
.BI \-\-debug \fR=\fPtype
Enable verbose tracing of various fio actions. May be `all' for all types
-or individual types separated by a comma (eg \-\-debug=io,file). `help' will
-list all available tracing options.
+or individual types separated by a comma (e.g. \-\-debug=file,mem will enable
+file and memory debugging). `help' will list all available tracing options.
+.TP
+.BI \-\-parse-only
+Parse options only, don't start any I/O.
.TP
.BI \-\-output \fR=\fPfilename
Write output to \fIfilename\fR.
Print statistics in selected mode AND terse, semicolon-delimited format.
Deprecated, use \-\-output-format instead to select multiple formats.
.TP
-.B \-\-version
-Display version information and exit.
-.TP
.BI \-\-terse\-version \fR=\fPversion
Set terse version output format (default 3, or 2, 4, 5)
.TP
+.B \-\-version
+Print version information and exit.
+.TP
.B \-\-help
-Display usage information and exit.
+Print a summary of the command line options and exit.
.TP
.B \-\-cpuclock-test
-Perform test and validation of internal CPU clock
+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
+.BI \-\-crctest \fR=\fP[test]
+Test the speed of the built-in checksumming functions. If no argument is given,
+all of them are tested. Alternatively, 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.
+Print help information for \fIcommand\fR. May be `all' for all commands.
.TP
.BI \-\-enghelp \fR=\fPioengine[,command]
List all commands defined by \fIioengine\fR, or print help for \fIcommand\fR defined by \fIioengine\fR.
+If no \fIioengine\fR is given, list all available ioengines.
.TP
.BI \-\-showcmd \fR=\fPjobfile
Convert \fIjobfile\fR to a set of command-line options.
.TP
+.BI \-\-readonly
+Turn on safety read-only checks, preventing writes. The \-\-readonly
+option is an extra safety guard to prevent users from accidentally starting
+a write workload when that is not desired. Fio will only write if
+`rw=write/randwrite/rw/randrw` is given. This extra safety net can be used
+as an extra precaution as \-\-readonly will also enable a write check in
+the I/O engine core to prevent writes due to unknown user space bug(s).
+.TP
.BI \-\-eta \fR=\fPwhen
-Specifies when real-time ETA estimate should be printed. \fIwhen\fR may
-be one of `always', `never' or `auto'.
+Specifies when real-time ETA estimate should be printed. \fIwhen\fR may
+be `always', `never' or `auto'.
.TP
.BI \-\-eta\-newline \fR=\fPtime
-Force an ETA newline for every `time` period passed.
+Force a new line for every \fItime\fR period passed. When the unit is omitted,
+the value is interpreted in seconds.
.TP
.BI \-\-status\-interval \fR=\fPtime
-Report full output status every `time` period passed.
-.TP
-.BI \-\-readonly
-Turn on safety read-only checks, preventing any attempted write.
-.TP
-.BI \-\-section \fR=\fPsec
-Only run section \fIsec\fR from job file. This option can be used multiple times to add more sections to run.
+Force full status dump every \fItime\fR period passed. When the unit is omitted,
+the value is interpreted in seconds.
+.TP
+.BI \-\-section \fR=\fPname
+Only run specified section \fIname\fR in job file. Multiple sections can be specified.
+The \-\-section option allows one to combine related jobs into one file.
+E.g. one job file could define light, moderate, and heavy sections. Tell
+fio to run only the "heavy" section by giving \-\-section=heavy
+command line option. One can also specify the "write" operations in one
+section and "verify" operation in another section. The \-\-section option
+only applies to job sections. The reserved *global* section is always
+parsed and used.
.TP
.BI \-\-alloc\-size \fR=\fPkb
-Set the internal smalloc pool size to \fIkb\fP kilobytes.
+Set the internal smalloc pool size to \fIkb\fP in KiB. The
+\-\-alloc-size switch allows one to use a larger pool size for smalloc.
+If running large jobs with randommap enabled, fio can run out of memory.
+Smalloc is an internal allocator for shared structures from a fixed size
+memory pool and can grow to 16 pools. The pool size defaults to 16MiB.
+NOTE: While running .fio_smalloc.* backing store files are visible
+in /tmp.
.TP
.BI \-\-warnings\-fatal
All fio parser warnings are fatal, causing fio to exit with an error.
.TP
.BI \-\-max\-jobs \fR=\fPnr
-Set the maximum allowed number of jobs (threads/processes) to support.
+Set the maximum number of threads/processes to support.
.TP
.BI \-\-server \fR=\fPargs
-Start a backend server, with \fIargs\fP specifying what to listen to. See client/server section.
+Start a backend server, with \fIargs\fP specifying what to listen to. See Client/Server section.
.TP
.BI \-\-daemonize \fR=\fPpidfile
-Background a fio server, writing the pid to the given pid file.
+Background a fio server, writing the pid to the given \fIpidfile\fP file.
.TP
-.BI \-\-client \fR=\fPhost
-Instead of running the jobs locally, send and run them on the given host or set of hosts. See client/server section.
+.BI \-\-client \fR=\fPhostname
+Instead of running the jobs locally, send and run them on the given host or set of hosts. See Client/Server section.
+.TP
+.BI \-\-remote-config \fR=\fPfile
+Tell fio server to load this local file.
.TP
.BI \-\-idle\-prof \fR=\fPoption
-Report cpu idleness on a system or percpu basis (\fIoption\fP=system,percpu) or run unit work calibration only (\fIoption\fP=calibrate).
+Report CPU idleness. \fIoption\fP is one of the following:
+.RS
+.RS
+.TP
+.B calibrate
+Run unit work calibration only and exit.
+.TP
+.B system
+Show aggregate system idleness and unit work.
+.TP
+.B percpu
+As "system" but also show per CPU idleness.
+.RE
+.RE
+.TP
+.BI \-\-inflate-log \fR=\fPlog
+Inflate and output compressed log.
+.TP
+.BI \-\-trigger-file \fR=\fPfile
+Execute trigger cmd when file exists.
+.TP
+.BI \-\-trigger-timeout \fR=\fPt
+Execute trigger at this time.
+.TP
+.BI \-\-trigger \fR=\fPcmd
+Set this command as local trigger.
+.TP
+.BI \-\-trigger-remote \fR=\fPcmd
+Set this command as remote trigger.
+.TP
+.BI \-\-aux-path \fR=\fPpath
+Use this path for fio state generated files.
.SH "JOB FILE FORMAT"
-Job files are in `ini' format. They consist of one or more
-job definitions, which begin with a job name in square brackets and
-extend to the next job name. The job name can be any ASCII string
-except `global', which has a special meaning. Following the job name is
-a sequence of zero or more parameters, one per line, that define the
-behavior of the job. Any line starting with a `;' or `#' character is
-considered a comment and ignored.
-.P
-If \fIjobfile\fR is specified as `-', the job file will be read from
-standard input.
-.SS "Global Section"
-The global section contains default parameters for jobs specified in the
-job file. A job is only affected by global sections residing above it,
-and there may be any number of global sections. Specific job definitions
-may override any parameter set in global sections.
-.SH "JOB PARAMETERS"
-.SS Types
-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:
+Any parameters following the options will be assumed to be job files, unless
+they match a job file parameter. Multiple job files can be listed and each job
+file will be regarded as a separate group. Fio will `stonewall` execution
+between each group.
+
+Fio accepts one or more job files describing what it is
+supposed to do. The job file format is the classic ini file, where the names
+enclosed in [] brackets define the job name. You are free to use any ASCII name
+you want, except *global* which has special meaning. Following the job name is
+a sequence of zero or more parameters, one per line, that define the behavior of
+the job. If the first character in a line is a ';' or a '#', the entire line is
+discarded as a comment.
+
+A *global* section sets defaults for the jobs described in that file. A job may
+override a *global* section parameter, and a job file may even have several
+*global* sections if so desired. A job is only affected by a *global* section
+residing above it.
+
+The \-\-cmdhelp option also lists all options. If used with an `option`
+argument, \-\-cmdhelp will detail the given `option`.
+
+See the `examples/` directory in the fio source for inspiration on how to write
+job files. Note the copyright and license requirements currently apply to
+`examples/` files.
+.SH "JOB FILE PARAMETERS"
+Some parameters take an option of a given type, such as an integer or a
+string. Anywhere a numeric value is required, an arithmetic expression may be
+used, provided it is surrounded by parentheses. Supported operators are:
.RS
.RS
.TP
.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:
+parentheses).
+.SH "PARAMETER TYPES"
+The following parameter types are used.
.TP
.I str
-String: a sequence of alphanumeric characters.
+String. A sequence of alphanumeric characters.
+.TP
+.I time
+Integer with possible time suffix. Without a unit value is interpreted as
+seconds unless otherwise specified. Accepts a suffix of 'd' for days, 'h' for
+hours, 'm' for minutes, 's' for seconds, 'ms' (or 'msec') for milliseconds and 'us'
+(or 'usec') for microseconds. For example, use 10m for 10 minutes.
.TP
.I int
Integer. A whole number value, which may contain an integer prefix
and an integer suffix.
-[integer prefix]number[integer suffix]
+[*integer prefix*] **number** [*integer suffix*]
-The optional integer prefix specifies the number's base. The default
-is decimal. 0x specifies hexadecimal.
+The optional *integer prefix* specifies the number's base. The default
+is decimal. *0x* specifies hexadecimal.
-The optional integer suffix specifies the number's units, and includes
-an optional unit prefix and an optional unit. For quantities
-of data, the default unit is bytes. For quantities of time,
-the default unit is seconds.
+The optional *integer suffix* specifies the number's units, and includes an
+optional unit prefix and an optional unit. For quantities of data, the
+default unit is bytes. For quantities of time, the default unit is seconds
+unless otherwise specified.
+
+With \fBkb_base=1000\fR, fio follows international standards for unit
+prefixes. To specify power-of-10 decimal values defined in the
+International System of Units (SI):
-With \fBkb_base=1000\fR, fio follows international standards for unit prefixes.
-To specify power-of-10 decimal values defined in the International
-System of Units (SI):
.nf
ki means kilo (K) or 1000
mi means mega (M) or 1000**2
.fi
To specify power-of-2 binary values defined in IEC 80000-13:
+
.nf
k means kibi (Ki) or 1024
m means mebi (Mi) or 1024**2
p means pebi (Pi) or 1024**5
.fi
-With \fBkb_base=1024\fR (the default), the unit prefixes are opposite from
-those specified in the SI and IEC 80000-13 standards to provide
-compatibility with old scripts. For example, 4k means 4096.
+With \fBkb_base=1024\fR (the default), the unit prefixes are opposite
+from those specified in the SI and IEC 80000-13 standards to provide
+compatibility with old scripts. For example, 4k means 4096.
+
+For quantities of data, an optional unit of 'B' may be included
+(e.g., 'kB' is the same as 'k').
+
+The *integer suffix* is not case sensitive (e.g., m/mi mean mebi/mega,
+not milli). 'b' and 'B' both mean byte, not bit.
-.nf
Examples with \fBkb_base=1000\fR:
+
+.nf
4 KiB: 4096, 4096b, 4096B, 4k, 4kb, 4kB, 4K, 4KB
1 MiB: 1048576, 1m, 1024k
1 MB: 1000000, 1mi, 1000ki
1 TB: 1000000000, 1ti, 1000mi, 1000000ki
.fi
-.nf
Examples with \fBkb_base=1024\fR (default):
+
+.nf
4 KiB: 4096, 4096b, 4096B, 4k, 4kb, 4kB, 4K, 4KB
1 MiB: 1048576, 1m, 1024k
1 MB: 1000000, 1mi, 1000ki
1 TB: 1000000000, 1ti, 1000mi, 1000000ki
.fi
-For quantities of data, an optional unit of 'B' may be included
-(e.g., 'kb' is the same as 'k').
-
-The integer suffix is not case sensitive (e.g., m/mi mean mebi/mega,
-not milli). 'b' and 'B' both mean byte, not bit.
-
To specify times (units are not case sensitive):
+
.nf
D means days
H means hours
us or usec means microseconds
.fi
+If the option accepts an upper and lower range, use a colon ':' or
+minus '-' to separate such values. See `irange` parameter type.
+If the lower value specified happens to be larger than the upper value
+the two values are swapped.
.TP
.I bool
-Boolean: a true or false value. `0' denotes false, `1' denotes true.
+Boolean. Usually parsed as an integer, however only defined for
+true and false (1 and 0).
.TP
.I irange
-Integer range: a range of integers specified in the format
-\fIlower\fR:\fIupper\fR or \fIlower\fR\-\fIupper\fR. \fIlower\fR and
-\fIupper\fR may contain a suffix as described above. If an option allows two
-sets of ranges, they are separated with a `,' or `/' character. For example:
-`8\-8k/8M\-4G'.
+Integer range with suffix. Allows value range to be given, such as
+1024-4096. A colon may also be used as the separator, e.g. 1k:4k. If the
+option allows two sets of ranges, they can be specified with a ',' or '/'
+delimiter: 1k-4k/8k-32k. Also see `int` parameter type.
.TP
.I float_list
-List of floating numbers: A list of floating numbers, separated by
-a ':' character.
-.SS "Parameter List"
+A list of floating point numbers, separated by a ':' character.
+.SH "JOB DESCRIPTION"
+With the above in mind, here follows the complete list of fio job parameters.
.TP
.BI name \fR=\fPstr
May be used to override the job name. On the command line, this parameter
.B none
Do not pre-allocate space.
.TP
+.B native
+Use a platform's native pre-allocation call but fall back to 'none' behavior if
+it fails/is not implemented.
+.TP
.B posix
Pre-allocate via \fBposix_fallocate\fR\|(3).
.TP
.RE
.P
May not be available on all supported platforms. 'keep' is only
-available on Linux. If using ZFS on Solaris this must be set to 'none'
-because ZFS doesn't support it. Default: 'posix'.
+available on Linux. If using ZFS on Solaris this cannot be set to 'posix'
+because ZFS doesn't support it. Default: 'native' if any pre-allocation methods
+are available, 'none' if not.
.RE
.TP
.BI fadvise_hint \fR=\fPstr
.B pareto
Use a pareto distribution to decide what file to access.
.TP
+.B normal
+Use a Gaussian (normal) distribution to decide what file to access.
+.TP
.B gauss
-Use a gaussian (normal) distribution to decide what file to access.
+Alias for normal.
.RE
.P
For \fBrandom\fR, \fBroundrobin\fR, and \fBsequential\fR, a postfix can be
Default: true.
.TP
.BI offset \fR=\fPint
-Start I/O at the provided offset in the file, given as either a fixed size or a
-percentage. If a percentage is given, the next \fBblockalign\fR-ed offset will
-be used. Data before the given offset will not be touched. This effectively
-caps the file size at (real_size - offset). Can be combined with \fBsize\fR to
-constrain the start and end range of the I/O workload.
+Start I/O at the provided offset in the file, given as either a fixed size in
+bytes or a percentage. If a percentage is given, the next \fBblockalign\fR-ed
+offset will be used. Data before the given offset will not be touched. This
+effectively caps the file size at (real_size - offset). Can be combined with
+\fBsize\fR to constrain the start and end range of the I/O workload. A percentage
+can be specified by a number between 1 and 100 followed by '%', for example,
+offset=20% to specify 20%.
.TP
.BI offset_increment \fR=\fPint
If this is provided, then the real offset becomes the
.B pareto
Pareto distribution
.TP
-.B gauss
-Normal (gaussian) distribution
+.B normal
+Normal (Gaussian) distribution
.TP
.B zoned
Zoned random distribution
that can be used visualize what the given input values will yield in terms of
hit rates. If you wanted to use \fBzipf\fR with a theta of 1.2, you would use
random_distribution=zipf:1.2 as the option. If a non-uniform model is used,
-fio will disable use of the random map. For the \fBgauss\fR distribution, a
-normal deviation is supplied as a value between 0 and 100.
+fio will disable use of the random map. For the \fBnormal\fR distribution, a
+normal (Gaussian) deviation is supplied as a value between 0 and 100.
.P
.RS
For a \fBzoned\fR distribution, fio supports specifying percentages of IO
on documentation by Jens Axboe.
.SH "REPORTING BUGS"
Report bugs to the \fBfio\fR mailing list <fio@vger.kernel.org>.
-See \fBREADME\fR.
+.br
+See \fBREPORTING-BUGS\fR.
+
+\fBREPORTING-BUGS\fR: http://git.kernel.dk/cgit/fio/plain/REPORTING-BUGS
.SH "SEE ALSO"
For further documentation see \fBHOWTO\fR and \fBREADME\fR.
.br
projects / fio.git / blobdiff