client connecting. To disable this behavior, set this option to 0.
.TP
.BI opendir \fR=\fPstr
-Recursively open any files below directory \fIstr\fR.
+Recursively open any files below directory \fIstr\fR. This accepts only a
+single directory and unlike related options, colons appearing in the path must
+not be escaped.
.TP
.BI lockfile \fR=\fPstr
Fio defaults to not locking any files before it does I/O to them. If a file
so. Default: false.
.TP
.BI max_open_zones \fR=\fPint
-A zone of a zoned block device is in the open state when it is partially written
-(i.e. not all sectors of the zone have been written). Zoned block devices may
-have limit a on the total number of zones that can be simultaneously in the
-open state, that is, the number of zones that can be written to simultaneously.
-The \fBmax_open_zones\fR parameter limits the number of zones to which write
-commands are issued by all fio jobs, that is, limits the number of zones that
-will be in the open state. This parameter is relevant only if the
-\fBzonemode=zbd\fR is used. The default value is always equal to maximum number
-of open zones of the target zoned block device and a value higher than this
-limit cannot be specified by users unless the option \fBignore_zone_limits\fR is
-specified. When \fBignore_zone_limits\fR is specified or the target device has
-no limit on the number of zones that can be in an open state,
+When a zone of a zoned block device is partially written (i.e. not all sectors
+of the zone have been written), the zone is in one of three
+conditions: 'implicit open', 'explicit open' or 'closed'. Zoned block devices
+may have a limit called 'max_open_zones' (same name as the parameter) on the
+total number of zones that can simultaneously be in the 'implicit open'
+or 'explicit open' conditions. Zoned block devices may have another limit
+called 'max_active_zones', on the total number of zones that can simultaneously
+be in the three conditions. The \fBmax_open_zones\fR parameter limits
+the number of zones to which write commands are issued by all fio jobs, that is,
+limits the number of zones that will be in the conditions. When the device has
+the max_open_zones limit and does not have the max_active_zones limit, the
+\fBmax_open_zones\fR parameter limits the number of zones in the two open
+conditions up to the limit. In this case, fio includes zones in the two open
+conditions to the write target zones at fio start. When the device has both the
+max_open_zones and the max_active_zones limits, the \fBmax_open_zones\fR
+parameter limits the number of zones in the three conditions up to the limit.
+In this case, fio includes zones in the three conditions to the write target
+zones at fio start.
+
+This parameter is relevant only if the \fBzonemode=zbd\fR is used. The default
+value is always equal to the max_open_zones limit of the target zoned block
+device and a value higher than this limit cannot be specified by users unless
+the option \fBignore_zone_limits\fR is specified. When \fBignore_zone_limits\fR
+is specified or the target device does not have the max_open_zones limit,
\fBmax_open_zones\fR can specify 0 to disable any limit on the number of zones
that can be simultaneously written to by all jobs.
.TP
.RE
.TP
.BI randrepeat \fR=\fPbool
-Seed the random number generator used for random I/O patterns in a
-predictable way so the pattern is repeatable across runs. Default: true.
+Seed all random number generators 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.
+Alias for \fBrandrepeat\fR. Default: true.
.TP
.BI randseed \fR=\fPint
Seed the random number generators based on this seed value, to be able to
.TP
.B random
Advise using FADV_RANDOM.
+.TP
+.B noreuse
+Advise using FADV_NOREUSE. This may be a no-op on older Linux
+kernels. Since Linux 6.3, it provides a hint to the LRU algorithm.
+See the \fBposix_fadvise\fR\|(2) man page.
.RE
.RE
.TP
to reads and writes. Comma-separated values may be specified for reads and
writes. See man \fBionice\fR\|(1). See also the \fBprioclass\fR option.
.TP
+.BI (io_uring,libaio)cmdprio_hint \fR=\fPint[,int]
+Set the I/O priority hint to use for I/Os that must be issued with a
+priority when \fBcmdprio_percentage\fR or \fBcmdprio_bssplit\fR is set.
+If not specified when \fBcmdprio_percentage\fR or \fBcmdprio_bssplit\fR
+is set, this defaults to 0 (no hint). A single value applies to reads and
+writes. Comma-separated values may be specified for reads and writes.
+See also the \fBpriohint\fR option.
+.TP
.BI (io_uring,libaio)cmdprio \fR=\fPint[,int]
Set the I/O priority value to use for I/Os that must be issued with a
priority when \fBcmdprio_percentage\fR or \fBcmdprio_bssplit\fR is set.
cmdprio_bssplit=blocksize/percentage:blocksize/percentage
.RE
.P
-In this case, each entry will use the priority class and priority level defined
-by the options \fBcmdprio_class\fR and \fBcmdprio\fR respectively.
+In this case, each entry will use the priority class, priority hint and
+priority level defined by the options \fBcmdprio_class\fR, \fBcmdprio\fR
+and \fBcmdprio_hint\fR respectively.
.P
The second accepted format for this option is:
.RS
does not restrict all entries to have the same priority class and priority
level.
.P
-For both formats, only the read and write data directions are supported, values
+The third accepted format for this option is:
+.RS
+.P
+cmdprio_bssplit=blocksize/percentage/class/level/hint:...
+.RE
+.P
+This is an extension of the second accepted format that allows to also
+specify a priority hint.
+.P
+For all formats, only the read and write data directions are supported, values
for trim IOs are ignored. This option is mutually exclusive with the
\fBcmdprio_percentage\fR option.
.RE
For direct I/O, requests will only succeed if cache invalidation isn't required,
file blocks are fully allocated and the disk request could be issued immediately.
.TP
-.BI (io_uring_cmd)fdp \fR=\fPbool
+.BI (io_uring_cmd,xnvme)fdp \fR=\fPbool
Enable Flexible Data Placement mode for write commands.
.TP
-.BI (io_uring_cmd)fdp_pli \fR=\fPstr
+.BI (io_uring_cmd,xnvme)fdp_pli_select \fR=\fPstr
+Defines how fio decides which placement ID to use next. The following types
+are defined:
+.RS
+.RS
+.TP
+.B random
+Choose a placement ID at random (uniform).
+.TP
+.B roundrobin
+Round robin over available placement IDs. This is the default.
+.RE
+.P
+The available placement ID index/indices is defined by \fBfdp_pli\fR option.
+.RE
+.TP
+.BI (io_uring_cmd,xnvme)fdp_pli \fR=\fPstr
Select which Placement ID Index/Indicies this job is allowed to use for writes.
By default, the job will cycle through all available Placement IDs, so use this
to isolate these identifiers to specific jobs. If you want fio to use placement
Enable the queue's completion eventfd even when unused. This may impact
performance. The default is to enable it only if
\fBlibblkio_wait_mode=eventfd\fR.
+.TP
+.BI (windowsaio)no_completion_thread
+Avoid using a separate thread for completion polling.
.SS "I/O depth"
.TP
.BI iodepth \fR=\fPint
kind of thinktime setting was used. If this option is set, then fio will
ignore the thinktime and continue doing IO at the specified rate, instead of
entering a catch-up mode after thinktime is done.
+.TP
+.BI rate_cycle \fR=\fPint
+Average bandwidth for \fBrate\fR and \fBrate_min\fR over this number
+of milliseconds. Defaults to 1000.
.SS "I/O latency"
.TP
.BI latency_target \fR=\fPtime
maximum latency. When the unit is omitted, the value is interpreted in
microseconds. Comma-separated values may be specified for reads, writes,
and trims as described in \fBblocksize\fR.
-.TP
-.BI rate_cycle \fR=\fPint
-Average bandwidth for \fBrate\fR and \fBrate_min\fR over this number
-of milliseconds. Defaults to 1000.
.SS "I/O replay"
.TP
.BI write_iolog \fR=\fPstr
priority setting, see the I/O engine specific `cmdprio_percentage` and
`cmdprio_class` options.
.TP
+.BI priohint \fR=\fPint
+Set the I/O priority hint. This is only applicable to platforms that support
+I/O priority classes and to devices with features controlled through priority
+hints, e.g. block devices supporting command duration limits, or CDL. CDL is a
+way to indicate the desired maximum latency of I/Os so that the device can
+optimize its internal command scheduling according to the latency limits
+indicated by the user. For per-I/O priority hint setting, see the I/O engine
+specific \fBcmdprio_hint\fB option.
+.TP
.BI cpus_allowed \fR=\fPstr
Controls the same options as \fBcpumask\fR, but accepts a textual
specification of the permitted CPUs instead and CPUs are indexed from 0. So
verification pass, according to the settings in the job file used. Default
false.
.TP
+.BI experimental_verify \fR=\fPbool
+Enable experimental verification. Standard verify records I/O metadata for
+later use during the verification phase. Experimental verify instead resets the
+file after the write phase and then replays I/Os for the verification phase.
+.TP
.BI trim_percentage \fR=\fPint
Number of verify blocks to discard/trim.
.TP
.TP
.BI trim_backlog_batch \fR=\fPint
Trim this number of I/O blocks.
-.TP
-.BI experimental_verify \fR=\fPbool
-Enable experimental verification. Standard verify records I/O metadata for
-later use during the verification phase. Experimental verify instead resets the
-file after the write phase and then replays I/Os for the verification phase.
.SS "Steady state"
.TP
.BI steadystate \fR=\fPstr:float "\fR,\fP ss" \fR=\fPstr:float
.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. When the unit is omitted, the
-value is interpreted in seconds.
+has been reached. Data will be collected every \fBss_interval\fR. The default
+is 0 which disables steady state detection. When the unit is omitted, the value
+is interpreted in seconds.
.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. When the unit is omitted, the value is interpreted in seconds.
+.TP
+.BI steadystate_check_interval \fR=\fPtime "\fR,\fP ss_interval" \fR=\fPtime
+The values suring the rolling window will be collected with a period of this
+value. If \fBss_interval\fR is 30s and \fBss_dur\fR is 300s, 10 measurements
+will be taken. Default is 1s but that might not converge, especially for slower
+devices, so set this accordingly. When the unit is omitted, the value is
+interpreted in seconds.
.SS "Measurements and reporting"
.TP
.BI per_job_logs \fR=\fPbool
when fio created the I/O unit to completion of the I/O operation.
.TP
.B bw
-Bandwidth statistics based on samples. Same names as the xlat stats,
-but also includes the number of samples taken (\fIsamples\fR) and an
-approximate percentage of total aggregate bandwidth this thread
-received in its group (\fIper\fR). This last value is only really
-useful if the threads in this group are on the same disk, since they
-are then competing for disk access.
+Bandwidth statistics based on measurements from discrete intervals. Fio
+continuosly monitors bytes transferred and I/O operations completed. By default
+fio calculates bandwidth in each half-second interval (see \fBbwavgtime\fR)
+and reports descriptive statistics for the measurements here. Same names as the
+xlat stats, but also includes the number of samples taken (\fIsamples\fR) and an
+approximate percentage of total aggregate bandwidth this thread received in its
+group (\fIper\fR). This last value is only really useful if the threads in this
+group are on the same disk, since they are then competing for disk access.
.TP
.B iops
-IOPS statistics based on samples. Same names as \fBbw\fR.
+IOPS statistics based on measurements from discrete intervals.
+For details see the description for \fBbw\fR above. See
+\fBiopsavgtime\fR to control the duration of the intervals.
+Same values reported here as for \fBbw\fR except for percentage.
.TP
.B lat (nsec/usec/msec)
The distribution of I/O completion latencies. This is the time from when
.P
.nf
Disk stats (read/write):
- sda: ios=16398/16511, merge=30/162, ticks=6853/819634, in_queue=826487, util=100.00%
+ sda: ios=16398/16511, sectors=32321/65472, merge=30/162, ticks=6853/819634, in_queue=826487, util=100.00%
.fi
.P
Each value is printed for both reads and writes, with reads first. The
projects / fio.git / blobdiff