-.TH fio 1 "December 2014" "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.
Limit run time to \fIruntime\fR seconds.
.TP
.B \-\-bandwidth\-log
-Generate per-job bandwidth logs.
+Generate aggregate bandwidth logs.
.TP
.B \-\-minimal
Print statistics in a terse, semicolon-delimited format.
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 (Current version 3, or older version 2).
+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=\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 \-\-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 \-\-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
-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. 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.
+Integer. A whole number value, which may contain an integer prefix
+and an 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 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):
+
+.nf
+ki means kilo (K) or 1000
+mi means mega (M) or 1000**2
+gi means giga (G) or 1000**3
+ti means tera (T) or 1000**4
+pi means peta (P) or 1000**5
+.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
+g means gibi (Gi) or 1024**3
+t means tebi (Ti) or 1024**4
+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.
+
+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.
+
+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 TiB: 1073741824, 1t, 1024m, 1048576k
+1 TB: 1000000000, 1ti, 1000mi, 1000000ki
+.fi
+
+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 TiB: 1073741824, 1t, 1024m, 1048576k
+1 TB: 1000000000, 1ti, 1000mi, 1000000ki
+.fi
+
+To specify times (units are not case sensitive):
+
+.nf
+D means days
+H means hours
+M mean minutes
+s or sec means seconds (default)
+ms or msec means milliseconds
+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
.RE
.P
.TP
+.BI unique_filename \fR=\fPbool
+To avoid collisions between networked clients, fio defaults to prefixing
+any generated filenames (with a directory specified) with the source of
+the client connecting. To disable this behavior, set this option to 0.
+.TP
.BI lockfile \fR=\fPstr
Fio defaults to not locking any files before it does IO to them. If a file or
file descriptor is shared, fio can serialize IO to that file to make the end
Sequential writes.
.TP
.B trim
-Sequential trim (Linux block devices only).
+Sequential trims (Linux block devices only).
.TP
.B randread
Random reads.
Random writes.
.TP
.B randtrim
-Random trim (Linux block devices only).
+Random trims (Linux block devices only).
.TP
.B rw, readwrite
Mixed sequential reads and writes.
Mixed random reads and writes.
.TP
.B trimwrite
-Trim and write mixed workload. Blocks will be trimmed first, then the same
-blocks will be written to.
+Sequential trim and write mixed workload. Blocks will be trimmed first, then
+the same blocks will be written to.
.RE
.P
+Fio defaults to read if the option is not specified.
For mixed I/O, the default split is 50/50. For certain types of io the result
may still be skewed a bit, since the speed may be different. It is possible to
-specify a number of IO's to do before getting a new offset, this is done by
+specify a number of IOs to do before getting a new offset, this is done by
appending a `:\fI<nr>\fR to the end of the string given. For a random read, it
would look like \fBrw=randread:8\fR for passing in an offset modifier with a
value of 8. If the postfix is used with a sequential IO pattern, then the value
.P
\fBsequential\fR is only useful for random IO, where fio would normally
generate a new random offset for every IO. If you append eg 8 to randread, you
-would get a new random offset for every 8 IO's. The result would be a seek for
-only every 8 IO's, instead of for every IO. Use \fBrw=randread:8\fR to specify
+would get a new random offset for every 8 IOs. The result would be a seek for
+only every 8 IOs, instead of for every IO. Use \fBrw=randread:8\fR to specify
that. As sequential IO is already sequential, setting \fBsequential\fR for that
would not result in any differences. \fBidentical\fR behaves in a similar
fashion, except it sends the same offset 8 number of times before generating a
.TP
.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
+reads, writes, and trims are accounted and reported separately. If this option is
set fio sums the results and reports them as "mixed" instead.
.TP
.BI randrepeat \fR=\fPbool
.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=\fPbool
+.BI fadvise_hint \fR=\fPstr
Use \fBposix_fadvise\fR\|(2) to advise the kernel what I/O patterns
-are likely to be issued. Default: true.
+are likely to be issued. Accepted values are:
+.RS
+.RS
+.TP
+.B 0
+Backwards compatible hint for "no hint".
+.TP
+.B 1
+Backwards compatible hint for "advise with fio workload type". This
+uses \fBFADV_RANDOM\fR for a random workload, and \fBFADV_SEQUENTIAL\fR
+for a sequential workload.
+.TP
+.B sequential
+Advise using \fBFADV_SEQUENTIAL\fR
+.TP
+.B random
+Advise using \fBFADV_RANDOM\fR
+.RE
+.RE
+.TP
+.BI write_hint \fR=\fPstr
+Use \fBfcntl\fR\|(2) to advise the kernel what life time to expect from a write.
+Only supported on Linux, as of version 4.13. The values are all relative to
+each other, and no absolute meaning should be associated with them. Accepted
+values are:
+.RS
+.RS
+.TP
+.B none
+No particular life time associated with this file.
.TP
-.BI fadvise_stream \fR=\fPint
-Use \fBposix_fadvise\fR\|(2) to advise the kernel what stream ID the
-writes issued belong to. Only supported on Linux. Note, this option
-may change going forward.
+.B short
+Data written to this file has a short life time.
+.TP
+.B medium
+Data written to this file has a medium life time.
+.TP
+.B long
+Data written to this file has a long life time.
+.TP
+.B extreme
+Data written to this file has a very long life time.
+.RE
+.RE
.TP
.BI size \fR=\fPint
Total size of I/O for this job. \fBfio\fR will run until this many bytes have
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
-either of which may be empty to leave that value at its default. If a trailing
-comma isn't given, the remainder will inherit the last value set.
-.TP
-.BI blocksize_range \fR=\fPirange[,irange] "\fR,\fB bsrange" \fR=\fPirange[,irange]
-Specify a range of I/O block sizes. The issued I/O unit will always be a
-multiple of the minimum size, unless \fBblocksize_unaligned\fR is set. Applies
-to both reads and writes if only one range is given, but can be specified
-separately with a comma separating the values. Example: bsrange=1k-4k,2k-8k.
-Also (see \fBblocksize\fR).
-.TP
-.BI bssplit \fR=\fPstr
+.BI blocksize \fR=\fPint[,int][,int] "\fR,\fB bs" \fR=\fPint[,int][,int]
+The block size in bytes for I/O units. Default: 4096.
+A single value applies to reads, writes, and trims.
+Comma-separated values may be specified for reads, writes, and trims.
+Empty values separated by commas use the default value. A value not
+terminated in a comma applies to subsequent types.
+.nf
+Examples:
+bs=256k means 256k for reads, writes and trims
+bs=8k,32k means 8k for reads, 32k for writes and trims
+bs=8k,32k, means 8k for reads, 32k for writes, and default for trims
+bs=,8k means default for reads, 8k for writes and trims
+bs=,8k, means default for reads, 8k for writes, and default for trims
+.fi
+.TP
+.BI blocksize_range \fR=\fPirange[,irange][,irange] "\fR,\fB bsrange" \fR=\fPirange[,irange][,irange]
+A range of block sizes in bytes for I/O units.
+The issued I/O unit will always be a multiple of the minimum size, unless
+\fBblocksize_unaligned\fR is set.
+Comma-separated ranges may be specified for reads, writes, and trims
+as described in \fBblocksize\fR.
+.nf
+Example: bsrange=1k-4k,2k-8k.
+.fi
+.TP
+.BI bssplit \fR=\fPstr[,str][,str]
This option allows even finer grained control of the block sizes issued,
not just even splits between them. With this option, you can weight various
block sizes for exact control of the issued IO for a job that has mixed
optionally adding as many definitions as needed separated by a colon.
Example: bssplit=4k/10:64k/50:32k/40 would issue 50% 64k blocks, 10% 4k
blocks and 40% 32k blocks. \fBbssplit\fR also supports giving separate
-splits to reads and writes. The format is identical to what the
-\fBbs\fR option accepts, the read and write parts are separated with a
-comma.
+splits to reads, writes, and trims.
+Comma-separated values may be specified for reads, writes, and trims
+as described in \fBblocksize\fR.
.TP
-.B blocksize_unaligned\fR,\fP bs_unaligned
-If set, any size in \fBblocksize_range\fR may be used. This typically won't
+.B blocksize_unaligned\fR,\fB bs_unaligned
+If set, fio will issue I/O units with any size within \fBblocksize_range\fR,
+not just multiples of the minimum size. This typically won't
work with direct I/O, as that normally requires sector alignment.
.TP
-.BI blockalign \fR=\fPint[,int] "\fR,\fB ba" \fR=\fPint[,int]
-At what boundary to align random IO offsets. Defaults to the same as 'blocksize'
-the minimum blocksize given. Minimum alignment is typically 512b
-for using direct IO, though it usually depends on the hardware block size.
-This option is mutually exclusive with using a random map for files, so it
-will turn off that option.
-.TP
.BI bs_is_seq_rand \fR=\fPbool
If this option is set, fio will use the normal read,write blocksize settings as
-sequential,random instead. Any random read or write will use the WRITE
-blocksize settings, and any sequential read or write will use the READ
-blocksize setting.
+sequential,random blocksize settings instead. Any random read or write will
+use the WRITE blocksize settings, and any sequential read or write will use
+the READ blocksize settings.
+.TP
+.BI blockalign \fR=\fPint[,int][,int] "\fR,\fB ba" \fR=\fPint[,int][,int]
+Boundary to which fio will align random I/O units. Default: \fBblocksize\fR.
+Minimum alignment is typically 512b for using direct IO, though it usually
+depends on the hardware block size. This option is mutually exclusive with
+using a random map for files, so it will turn off that option.
+Comma-separated values may be specified for reads, writes, and trims
+as described in \fBblocksize\fR.
.TP
.B zero_buffers
Initialize buffers with all zeros. Default: fill buffers with random data.
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
-"", e.g.:
+If set, fio will fill the I/O buffers with this pattern or with the contents
+of a file. If not set, the contents of I/O buffers are 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 ``""``. Or it may also be a filename,
+where the filename must be wrapped with ``''`` in which case the file is
+opened and read. Note that not all the file contents will be read if that
+would cause the buffers to overflow. So, for example:
+.RS
.RS
+\fBbuffer_pattern\fR='filename'
.RS
+or
+.RE
\fBbuffer_pattern\fR="abcd"
.RS
or
Also you can combine everything together in any order:
.LP
.RS
-\fBbuffer_pattern\fR=0xdeadface"abcd"-12
+\fBbuffer_pattern\fR=0xdeadface"abcd"-12'filename'
.RE
.RE
.TP
.TP
.B sequential
Do each file in the set sequentially.
+.TP
+.B zipf
+Use a zipfian distribution to decide what file to access.
+.TP
+.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
+Alias for normal.
.RE
.P
-The number of I/Os to issue before switching to a new file can be specified by
-appending `:\fIint\fR' to the service type.
+For \fBrandom\fR, \fBroundrobin\fR, and \fBsequential\fR, a postfix can be
+appended to tell fio how many I/Os to issue before switching to a new file.
+For example, specifying \fBfile_service_type=random:8\fR would cause fio to
+issue \fI8\fR I/Os before selecting a new file at random. For the non-uniform
+distributions, a floating point postfix can be given to influence how the
+distribution is skewed. See \fBrandom_distribution\fR for a description of how
+that would work.
.RE
.TP
.BI ioengine \fR=\fPstr
.TP
.B psync
Basic \fBpread\fR\|(2) or \fBpwrite\fR\|(2) I/O.
+Default on all supported operating systems except for Windows.
.TP
.B vsync
Basic \fBreadv\fR\|(2) or \fBwritev\fR\|(2) I/O. Will emulate queuing by
Solaris native asynchronous I/O.
.TP
.B windowsaio
-Windows native asynchronous I/O.
+Windows native asynchronous I/O. Default on Windows.
.TP
.B mmap
File is memory mapped with \fBmmap\fR\|(2) and data copied using
\fBsplice\fR\|(2) is used to transfer the data and \fBvmsplice\fR\|(2) to
transfer data from user-space to the kernel.
.TP
-.B syslet-rw
-Use the syslet system calls to make regular read/write asynchronous.
-.TP
.B sg
SCSI generic sg v3 I/O. May be either synchronous using the SG_IO ioctl, or if
the target is an sg character device, we use \fBread\fR\|(2) and
.TP
.B cpuio
Doesn't transfer any data, but burns CPU cycles according to \fBcpuload\fR and
-\fBcpucycles\fR parameters.
+\fBcpuchunks\fR parameters. A job never finishes unless there is at least one
+non-cpuio job.
.TP
.B guasi
The GUASI I/O engine is the Generic Userspace Asynchronous Syscall Interface
Read, write and erase an MTD character device (e.g., /dev/mtd0). Discards are
treated as erases. Depending on the underlying device type, the I/O may have
to go in a certain pattern, e.g., on NAND, writing sequentially to erase blocks
-and discarding before overwriting. The writetrim mode works well for this
+and discarding before overwriting. The trimwrite mode works well for this
constraint.
+.TP
+.B pmemblk
+Read and write using filesystem DAX to a file on a filesystem mounted with
+DAX on a persistent memory device through the NVML libpmemblk library.
+.TP
+.B dev-dax
+Read and write using device DAX to a persistent memory device
+(e.g., /dev/dax0.0) through the NVML libpmem library.
.RE
.P
.RE
\fBiodepth_batch_complete_max\fR=<iodepth>
.RE
-which means that we will retrieve at leat 1 IO and up to the
+which means that we will retrieve at least 1 IO and up to the
whole submitted queue depth. If none of IO has been completed
yet, we will wait.
Default: true.
.TP
.BI offset \fR=\fPint
-Offset in the file to start I/O. Data before the offset will not be touched.
+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
SYNC_FILE_RANGE_WRITE
.TP
.B wait_after
-SYNC_FILE_RANGE_WRITE
+SYNC_FILE_RANGE_WAIT_AFTER
.TP
.RE
.P
.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
30% of accesses should be to the next 20%
.RE
.RS
-8% of accesses should be to to the next 30%
+8% of accesses should be to the next 30%
.RE
.RS
2% of accesses should be to the next 40%
writes, and trims. If just one set is given, it'll apply to all of them.
.RE
.TP
-.BI percentage_random \fR=\fPint
+.BI percentage_random \fR=\fPint[,int][,int]
For a random workload, set how big a percentage should be random. This defaults
to 100%, in which case the workload is fully random. It can be set from
anywhere from 0 to 100. Setting it to 0 would make the workload fully
words, this setting effectively caps the queue depth if the latter is larger.
Default: 1.
.TP
-.BI rate \fR=\fPint
+.BI rate \fR=\fPint[,int][,int]
Cap bandwidth used by this job. The number is in bytes/sec, the normal postfix
rules apply. You can use \fBrate\fR=500k to limit reads and writes to 500k each,
-or you can specify read and writes separately. Using \fBrate\fR=1m,500k would
-limit reads to 1MB/sec and writes to 500KB/sec. Capping only reads or writes
+or you can specify reads, write, and trim limits separately.
+Using \fBrate\fR=1m,500k would
+limit reads to 1MiB/sec and writes to 500KiB/sec. Capping only reads or writes
can be done with \fBrate\fR=,500k or \fBrate\fR=500k,. The former will only
-limit writes (to 500KB/sec), the latter will only limit reads.
+limit writes (to 500KiB/sec), the latter will only limit reads.
.TP
-.BI rate_min \fR=\fPint
+.BI rate_min \fR=\fPint[,int][,int]
Tell \fBfio\fR to do whatever it can to maintain at least the given bandwidth.
Failing to meet this requirement will cause the job to exit. The same format
-as \fBrate\fR is used for read vs write separation.
+as \fBrate\fR is used for read vs write vs trim separation.
.TP
-.BI rate_iops \fR=\fPint
+.BI rate_iops \fR=\fPint[,int][,int]
Cap the bandwidth to this number of IOPS. Basically the same as rate, just
specified independently of bandwidth. The same format as \fBrate\fR is used for
-read vs write separation. If \fBblocksize\fR is a range, the smallest block
+read vs write vs trim separation. If \fBblocksize\fR is a range, the smallest block
size is used as the metric.
.TP
-.BI rate_iops_min \fR=\fPint
+.BI rate_iops_min \fR=\fPint[,int][,int]
If this rate of I/O is not met, the job will exit. The same format as \fBrate\fR
-is used for read vs write separation.
+is used for read vs write vs trim separation.
.TP
.BI rate_process \fR=\fPstr
This option controls how fio manages rated IO submissions. The default is
that the \fBramp_time\fR is considered lead in time for a job, thus it will
increase the total runtime if a special timeout or runtime is specified.
.TP
+.BI steadystate \fR=\fPstr:float "\fR,\fP ss" \fR=\fPstr:float
+Define the criterion and limit for assessing steady state performance. The
+first parameter designates the criterion whereas the second parameter sets the
+threshold. When the criterion falls below the threshold for the specified
+duration, the job will stop. For example, iops_slope:0.1% will direct fio
+to terminate the job when the least squares regression slope falls below 0.1%
+of the mean IOPS. If group_reporting is enabled this will apply to all jobs in
+the group. All assessments are carried out using only data from the rolling
+collection window. Threshold limits can be expressed as a fixed value or as a
+percentage of the mean in the collection window. Below are the available steady
+state assessment criteria.
+.RS
+.RS
+.TP
+.B iops
+Collect IOPS data. Stop the job if all individual IOPS measurements are within
+the specified limit of the mean IOPS (e.g., iops:2 means that all individual
+IOPS values must be within 2 of the mean, whereas iops:0.2% means that all
+individual IOPS values must be within 0.2% of the mean IOPS to terminate the
+job).
+.TP
+.B iops_slope
+Collect IOPS data and calculate the least squares regression slope. Stop the
+job if the slope falls below the specified limit.
+.TP
+.B bw
+Collect bandwidth data. Stop the job if all individual bandwidth measurements
+are within the specified limit of the mean bandwidth.
+.TP
+.B bw_slope
+Collect bandwidth data and calculate the least squares regression slope. Stop
+the job if the slope falls below the specified limit.
+.RE
+.RE
+.TP
+.BI steadystate_duration \fR=\fPtime "\fR,\fP ss_dur" \fR=\fPtime
+A rolling window of this duration will be used to judge whether steady state
+has been reached. Data will be collected once per second. The default is 0
+which disables steady state detection.
+.TP
+.BI steadystate_ramp_time \fR=\fPtime "\fR,\fP ss_ramp" \fR=\fPtime
+Allow the job to run for the specified duration before beginning data collection
+for checking the steady state job termination criterion. The default is 0.
+.TP
.BI invalidate \fR=\fPbool
Invalidate buffer-cache for the file prior to starting I/O. Default: true.
.TP
.RS
.TP
.B malloc
-Allocate memory with \fBmalloc\fR\|(3).
+Allocate memory with \fBmalloc\fR\|(3). Default memory type.
.TP
.B shm
Use shared memory buffers allocated through \fBshmget\fR\|(2).
.TP
.B mmapshared
Same as \fBmmap\fR, but use a MMAP_SHARED mapping.
+.TP
+.B cudamalloc
+Use GPU memory as the buffers for GPUDirect RDMA benchmark. The ioengine must be \fBrdma\fR.
.RE
.P
The amount of memory allocated is the maximum allowed \fBblocksize\fR for the
.TP
.BI hugepage\-size \fR=\fPint
Defines the size of a huge page. Must be at least equal to the system setting.
-Should be a multiple of 1MB. Default: 4MB.
+Should be a multiple of 1MiB. Default: 4MiB.
.TP
.B exitall
Terminate all jobs when one finishes. Default: wait for each job to finish.
to finish.
.TP
.BI bwavgtime \fR=\fPint
-Average bandwidth calculations over the given time in milliseconds. Default:
-500ms.
+Average bandwidth calculations over the given time in milliseconds. If the job
+also does bandwidth logging through \fBwrite_bw_log\fR, then the minimum of
+this option and \fBlog_avg_msec\fR will be used. Default: 500ms.
.TP
.BI iopsavgtime \fR=\fPint
-Average IOPS calculations over the given time in milliseconds. Default:
-500ms.
+Average IOPS calculations over the given time in milliseconds. If the job
+also does IOPS logging through \fBwrite_iops_log\fR, then the minimum of
+this option and \fBlog_avg_msec\fR will be used. Default: 500ms.
.TP
.BI create_serialize \fR=\fPbool
If true, serialize file creation for the jobs. Default: true.
.BI unlink \fR=\fPbool
Unlink job files when done. Default: false.
.TP
+.BI unlink_each_loop \fR=\fPbool
+Unlink job files after each iteration or loop. Default: false.
+.TP
.BI loops \fR=\fPint
Specifies the number of iterations (runs of the same workload) of this job.
Default: 1.
.RS
.RS
.TP
-.B md5 crc16 crc32 crc32c crc32c-intel crc64 crc7 sha256 sha512 sha1 xxhash
+.B md5 crc16 crc32 crc32c crc32c-intel crc64 crc7 sha256 sha512 sha1 sha3-224 sha3-256 sha3-384 sha3-512 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.
decimal or a hex number). The verify_pattern if larger than a 32-bit quantity
has to be a hex number that starts with either "0x" or "0X". Use with
\fBverify\fP=str. Also, verify_pattern supports %o format, which means that for
-each block offset will be written and then verifyied back, e.g.:
+each block offset will be written and then verified back, e.g.:
.RS
.RS
\fBverify_pattern\fR=%o
Start a new reporting group. If not given, all jobs in a file will be part
of the same reporting group, unless separated by a stonewall.
.TP
+.BI stats \fR=\fPbool
+By default, fio collects and shows final output results for all jobs that run.
+If this option is set to 0, then fio will ignore it in the final stat output.
+.TP
.BI numjobs \fR=\fPint
Number of clones (processes/threads performing the same workload) of this job.
Default: 1.
not set, jobs with identical names will share the log filename. Default: true.
.TP
.BI write_bw_log \fR=\fPstr
-If given, write a bandwidth log of the jobs in this job file. Can be used to
-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.x.log, where x is the index of the job (1..N,
-where N is the number of jobs). If \fBper_job_logs\fR is false, then the
-filename will not include the job index. See the \fBLOG FILE FORMATS\fR
+If given, write a bandwidth log for this job. Can be used to 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.x.log,
+where x is the index of the job (1..N, where N is the number of jobs). If
+\fBper_job_logs\fR is false, then the filename will not include the job index.
+See the \fBLOG FILE FORMATS\fR
section.
.TP
.BI write_lat_log \fR=\fPstr
append the type of log. If \fBper_job_logs\fR is false, then the filename will
not include the job index. See the \fBLOG FILE FORMATS\fR section.
.TP
+.BI write_hist_log \fR=\fPstr
+Same as \fBwrite_lat_log\fR, but writes I/O completion latency histograms. If
+no filename is given with this option, the default filename of
+"jobname_clat_hist.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. If \fBper_job_logs\fR is false, then the filename will not
+include the job index. See the \fBLOG FILE FORMATS\fR section.
+.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.x.log" is used, where x is the
IO that completes. When writing to the disk log, that can quickly grow to a
very large size. Setting this option makes fio average the each log entry
over the specified period of time, reducing the resolution of the log. See
-\fBlog_max\fR as well. Defaults to 0, logging all entries.
+\fBlog_max_value\fR as well. Defaults to 0, logging all entries.
.TP
-.BI log_max \fR=\fPbool
+.BI log_max_value \fR=\fPbool
If \fBlog_avg_msec\fR is set, fio logs the average over that window. If you
instead want to log the maximum value, set this option to 1. Defaults to
0, meaning that averaged values are logged.
.TP
+.BI log_hist_msec \fR=\fPint
+Same as \fBlog_avg_msec\fR, but logs entries for completion latency histograms.
+Computing latency percentiles from averages of intervals using \fBlog_avg_msec\fR
+is innacurate. Setting this option makes fio log histogram entries over the
+specified period of time, reducing log sizes for high IOPS devices while
+retaining percentile accuracy. See \fBlog_hist_coarseness\fR as well. Defaults
+to 0, meaning histogram logging is disabled.
+.TP
+.BI log_hist_coarseness \fR=\fPint
+Integer ranging from 0 to 6, defining the coarseness of the resolution of the
+histogram logs enabled with \fBlog_hist_msec\fR. For each increment in
+coarseness, fio outputs half as many bins. Defaults to 0, for which histogram
+logs contain 1216 latency bins. See the \fBLOG FILE FORMATS\fR section.
+.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.
+entry as well as the other data values. Defaults to 0 meaning that offsets are
+not present in logs. See the \fBLOG FILE FORMATS\fR section.
.TP
.BI log_compression \fR=\fPint
If this is set, fio will compress the IO logs as it goes, to keep the memory
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 log_unix_epoch \fR=\fPbool
+If set, fio will log Unix timestamps to the log files produced by enabling
+\fBwrite_type_log\fR for each log type, instead of the default zero-based
+timestamps.
+.TP
.BI block_error_percentiles \fR=\fPbool
If set, record errors in trim block-sized units from writes and trims and output
a histogram of how many trims it took to get to errors, and what kind of error
used identically to normal parameters, with the caveat that when used on the
command line, they must come after the ioengine.
.TP
-.BI (cpu)cpuload \fR=\fPint
+.BI (cpuio)cpuload \fR=\fPint
Attempt to use the specified percentage of CPU cycles.
.TP
-.BI (cpu)cpuchunks \fR=\fPint
+.BI (cpuio)cpuchunks \fR=\fPint
Split the load into cycles of the given time. In microseconds.
.TP
-.BI (cpu)exit_on_io_done \fR=\fPbool
+.BI (cpuio)exit_on_io_done \fR=\fPbool
Detect when IO threads are done, then exit.
.TP
.BI (libaio)userspace_reap
enabled when polling for a minimum of 0 events (eg when
iodepth_batch_complete=0).
.TP
-.BI (psyncv2)hipri
+.BI (pvsync2)hipri
Set RWF_HIPRI on IO, indicating to the kernel that it's of
higher priority than normal.
.TP
connections rather than initiating an outgoing connection. The
hostname must be omitted if this option is used.
.TP
-.BI (net, pingpong) \fR=\fPbool
+.BI (net,netsplice)pingpong \fR=\fPbool
Normally a network writer will just continue writing data, and a network reader
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.
send back. For UDP multicast traffic pingpong=1 should only be set for a single
reader when multiple readers are listening to the same address.
.TP
-.BI (net, window_size) \fR=\fPint
+.BI (net,netsplice)window_size \fR=\fPint
Set the desired socket buffer size for the connection.
.TP
-.BI (net, mss) \fR=\fPint
+.BI (net,netsplice)mss \fR=\fPint
Set the TCP maximum segment size (TCP_MAXSEG).
.TP
-.BI (e4defrag,donorname) \fR=\fPstr
+.BI (e4defrag)donorname \fR=\fPstr
File will be used as a block donor (swap extents between files)
.TP
-.BI (e4defrag,inplace) \fR=\fPint
+.BI (e4defrag)inplace \fR=\fPint
Configure donor file block allocation strategy
.RS
.BI 0(default) :
allocate space immediately inside defragment event, and free right after event
.RE
.TP
+.BI (rbd)clustername \fR=\fPstr
+Specifies the name of the ceph cluster.
+.TP
.BI (rbd)rbdname \fR=\fPstr
Specifies the name of the RBD.
.TP
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.
+Specifies the username (without the 'client.' prefix) used to access the Ceph
+cluster. If the clustername is specified, the clientname shall be the full
+type.id string. If no type. prefix is given, fio will add 'client.' by default.
.TP
.BI (mtd)skipbad \fR=\fPbool
Skip operations against known bad blocks.
example:
.RS
.P
-Threads: 1: [_r] [24.8% done] [ 13509/ 8334 kb/s] [eta 00h:01m:31s]
+Jobs: 1: [_r] [24.8% done] [ 13509/ 8334 kb/s] [eta 00h:01m:31s]
.RE
.P
The characters in the first set of brackets denote the current status of each
Number of I/Os performed by all groups.
.TP
.B merge
-Number of merges in the I/O scheduler.
+Number of merges performed by the I/O scheduler.
.TP
.B ticks
Number of ticks we kept the disk busy.
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:
+change. Numbers in brackets (e.g. "[v3]") indicate which terse version
+introduced a field. The fields are:
.P
.RS
-.B terse version, fio version, jobname, groupid, error
+.B terse version, fio version [v3], jobname, groupid, error
.P
Read status:
.RS
-.B Total I/O \fR(KB)\fP, bandwidth \fR(KB/s)\fP, IOPS, runtime \fR(ms)\fP
+.B Total I/O \fR(KiB)\fP, bandwidth \fR(KiB/s)\fP, IOPS, runtime \fR(ms)\fP
.P
Submission latency:
.RS
.RE
Bandwidth:
.RS
-.B min, max, aggregate percentage of total, mean, standard deviation
+.B min, max, aggregate percentage of total, mean, standard deviation, number of samples [v5]
+.RE
+IOPS [v5]:
+.RS
+.B min, max, mean, standard deviation, number of samples
.RE
.RE
.P
Write status:
.RS
-.B Total I/O \fR(KB)\fP, bandwidth \fR(KB/s)\fP, IOPS, runtime \fR(ms)\fP
+.B Total I/O \fR(KiB)\fP, bandwidth \fR(KiB/s)\fP, IOPS, runtime \fR(ms)\fP
.P
Submission latency:
.RS
.RE
Bandwidth:
.RS
-.B min, max, aggregate percentage of total, mean, standard deviation
+.B min, max, aggregate percentage of total, mean, standard deviation, number of samples [v5]
.RE
+IOPS [v5]:
+.RS
+.B min, max, mean, standard deviation, number of samples
+.RE
+.RE
+.P
+Trim status [all but version 3]:
+.RS
+Similar to Read/Write status but for trims.
.RE
.P
CPU usage:
.RE
.RE
.P
-Disk utilization (1 for each disk used):
+Disk utilization (1 for each disk used) [v3]:
.RS
.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
.RE
.P
.B text description (if provided in config - appears on newline)
.RE
+.P
+Below is a single line containing short names for each of the fields in
+the minimal output v3, separated by semicolons:
+.RS
+.P
+.nf
+terse_version_3;fio_version;jobname;groupid;error;read_kb;read_bandwidth;read_iops;read_runtime_ms;read_slat_min;read_slat_max;read_slat_mean;read_slat_dev;read_clat_max;read_clat_min;read_clat_mean;read_clat_dev;read_clat_pct01;read_clat_pct02;read_clat_pct03;read_clat_pct04;read_clat_pct05;read_clat_pct06;read_clat_pct07;read_clat_pct08;read_clat_pct09;read_clat_pct10;read_clat_pct11;read_clat_pct12;read_clat_pct13;read_clat_pct14;read_clat_pct15;read_clat_pct16;read_clat_pct17;read_clat_pct18;read_clat_pct19;read_clat_pct20;read_tlat_min;read_lat_max;read_lat_mean;read_lat_dev;read_bw_min;read_bw_max;read_bw_agg_pct;read_bw_mean;read_bw_dev;write_kb;write_bandwidth;write_iops;write_runtime_ms;write_slat_min;write_slat_max;write_slat_mean;write_slat_dev;write_clat_max;write_clat_min;write_clat_mean;write_clat_dev;write_clat_pct01;write_clat_pct02;write_clat_pct03;write_clat_pct04;write_clat_pct05;write_clat_pct06;write_clat_pct07;write_clat_pct08;write_clat_pct09;write_clat_pct10;write_clat_pct11;write_clat_pct12;write_clat_pct13;write_clat_pct14;write_clat_pct15;write_clat_pct16;write_clat_pct17;write_clat_pct18;write_clat_pct19;write_clat_pct20;write_tlat_min;write_lat_max;write_lat_mean;write_lat_dev;write_bw_min;write_bw_max;write_bw_agg_pct;write_bw_mean;write_bw_dev;cpu_user;cpu_sys;cpu_csw;cpu_mjf;pu_minf;iodepth_1;iodepth_2;iodepth_4;iodepth_8;iodepth_16;iodepth_32;iodepth_64;lat_2us;lat_4us;lat_10us;lat_20us;lat_50us;lat_100us;lat_250us;lat_500us;lat_750us;lat_1000us;lat_2ms;lat_4ms;lat_10ms;lat_20ms;lat_50ms;lat_100ms;lat_250ms;lat_500ms;lat_750ms;lat_1000ms;lat_2000ms;lat_over_2000ms;disk_name;disk_read_iops;disk_write_iops;disk_read_merges;disk_write_merges;disk_read_ticks;write_ticks;disk_queue_time;disk_util
+.fi
+.RE
.SH TRACE FILE FORMAT
There are two trace file format that you can encounter. The older (v1) format
is unsupported since version 1.20-rc3 (March 2008). It will still be described
.B Trace file format v2
.RS
The second version of the trace file format was added in Fio version 1.17.
-It allows to access more then one file per trace and has a bigger set of
+It allows one to access more then one file per trace and has a bigger set of
possible file actions.
The first line of the trace file has to be:
Fio supports a variety of log file formats, for logging latencies, bandwidth,
and IOPS. The logs share a common format, which looks like this:
-.B time (msec), value, data direction, offset
+.B time (msec), value, data direction, block size (bytes), offset (bytes)
Time for the log entry is always in milliseconds. The value logged depends
on the type of log, it will be one of the following:
Value is in latency in usecs
.TP
.B Bandwidth log
-Value is in KB/sec
+Value is in KiB/sec
.TP
.B IOPS log
Value is in IOPS
.PD
.P
-The \fIoffset\fR is the offset, in bytes, from the start of the file, for that
-particular IO. The logging of the offset can be toggled with \fBlog_offset\fR.
+The entry's *block size* is always in bytes. The \fIoffset\fR is the offset, in
+bytes, from the start of the file, for that particular IO. The logging of the
+offset can be toggled with \fBlog_offset\fR.
-If windowed logging is enabled though \fBlog_avg_msec\fR, then fio doesn't log
+If windowed logging is enabled through \fBlog_avg_msec\fR, then fio doesn't log
individual IOs. Instead of logs the average values over the specified
-period of time. Since \fIdata direction\fR and \fIoffset\fR are per-IO values,
-they aren't applicable if windowed logging is enabled. If windowed logging
-is enabled and \fBlog_max_value\fR is set, then fio logs maximum values in
-that window instead of averages.
+period of time. Since \fIdata direction\fR, \fIblock size\fR and \fIoffset\fR
+are per-IO values, if windowed logging is enabled they aren't applicable and
+will be 0. If windowed logging is enabled and \fBlog_max_value\fR is set, then
+fio logs maximum values in that window instead of averages.
+
+For histogram logging the logs look like this:
+
+.B time (msec), data direction, block-size, bin 0, bin 1, ..., bin 1215
+
+Where 'bin i' gives the frequency of IO requests with a latency falling in
+the i-th bin. See \fBlog_hist_coarseness\fR for logging fewer bins.
.RE
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
Sample jobfiles are available in the \fBexamples\fR directory.
+.br
+These are typically located under /usr/share/doc/fio.
+
+\fBHOWTO\fR: http://git.kernel.dk/cgit/fio/plain/HOWTO
+.br
+\fBREADME\fR: http://git.kernel.dk/cgit/fio/plain/README
+.br
projects / fio.git / blobdiff