Limit on the number of simultaneously opened zones per single
thread/process.
+.. option:: ignore_zone_limits=bool
+ If this option is used, fio will ignore the maximum number of open
+ zones limit of the zoned block device in use, thus allowing the
+ option :option:`max_open_zones` value to be larger than the device
+ reported limit. Default: false.
+
.. option:: zone_reset_threshold=float
A number between zero and one that indicates the ratio of logical
.. option:: fdatasync=int
Like :option:`fsync` but uses :manpage:`fdatasync(2)` to only sync data and
- not metadata blocks. In Windows, FreeBSD, DragonFlyBSD or OSX there is no
+ not metadata blocks. In Windows, DragonFlyBSD or OSX there is no
:manpage:`fdatasync(2)` so this falls back to using :manpage:`fsync(2)`.
Defaults to 0, which means fio does not periodically issue and wait for a
data-only sync to complete.
.. option:: filesize=irange(int)
- Individual file sizes. May be a range, in which case fio will select sizes
- for files at random within the given range and limited to :option:`size` in
- total (if that is given). If not given, each created file is the same size.
- This option overrides :option:`size` in terms of file size, which means
- this value is used as a fixed size or possible range of each file.
+ Individual file sizes. May be a range, in which case fio will select sizes for
+ files at random within the given range. If not given, each created file is the
+ same size. This option overrides :option:`size` in terms of file size, i.e. if
+ :option:`filesize` is specified then :option:`size` becomes merely the default
+ for :option:`io_size` and has no effect at all if :option:`io_size` is set
+ explicitly.
.. option:: file_append=bool
with the caveat that when used on the command line, they must come after the
:option:`ioengine` that defines them is selected.
-.. option:: cmdprio_percentage=int : [io_uring] [libaio]
-
- Set the percentage of I/O that will be issued with higher priority by setting
- the priority bit. Non-read I/O is likely unaffected by ``cmdprio_percentage``.
- This option cannot be used with the `prio` or `prioclass` options. For this
- option to set the priority bit properly, NCQ priority must be supported and
- enabled and :option:`direct`\=1 option must be used. fio must also be run as
- the root user.
+.. option:: cmdprio_percentage=int[,int] : [io_uring] [libaio]
+
+ Set the percentage of I/O that will be issued with the highest priority.
+ Default: 0. A single value applies to reads and writes. Comma-separated
+ values may be specified for reads and writes. For this option to be
+ effective, NCQ priority must be supported and enabled, and `direct=1'
+ option must be used. fio must also be run as the root user. Unlike
+ slat/clat/lat stats, which can be tracked and reported independently, per
+ priority stats only track and report a single type of latency. By default,
+ completion latency (clat) will be reported, if :option:`lat_percentiles` is
+ set, total latency (lat) will be reported.
+
+.. option:: cmdprio_class=int[,int] : [io_uring] [libaio]
+
+ Set the I/O priority class to use for I/Os that must be issued with
+ a priority when :option:`cmdprio_percentage` or
+ :option:`cmdprio_bssplit` is set. If not specified when
+ :option:`cmdprio_percentage` or :option:`cmdprio_bssplit` is set,
+ this defaults to the highest priority class. A single value applies
+ to reads and writes. Comma-separated values may be specified for
+ reads and writes. See :manpage:`ionice(1)`. See also the
+ :option:`prioclass` option.
+
+.. option:: cmdprio=int[,int] : [io_uring] [libaio]
+
+ Set the I/O priority value to use for I/Os that must be issued with
+ a priority when :option:`cmdprio_percentage` or
+ :option:`cmdprio_bssplit` is set. If not specified when
+ :option:`cmdprio_percentage` or :option:`cmdprio_bssplit` is set,
+ this defaults to 0.
+ Linux limits us to a positive value between 0 and 7, with 0 being the
+ highest. A single value applies to reads and writes. Comma-separated
+ values may be specified for reads and writes. See :manpage:`ionice(1)`.
+ Refer to an appropriate manpage for other operating systems since
+ meaning of priority may differ. See also the :option:`prio` option.
+
+.. option:: cmdprio_bssplit=str[,str] : [io_uring] [libaio]
+ To get a finer control over I/O priority, this option allows
+ specifying the percentage of IOs that must have a priority set
+ depending on the block size of the IO. This option is useful only
+ when used together with the :option:`bssplit` option, that is,
+ multiple different block sizes are used for reads and writes.
+
+ The first accepted format for this option is the same as the format of
+ the :option:`bssplit` option:
+
+ cmdprio_bssplit=blocksize/percentage:blocksize/percentage
+
+ In this case, each entry will use the priority class and priority
+ level defined by the options :option:`cmdprio_class` and
+ :option:`cmdprio` respectively.
+
+ The second accepted format for this option is:
+
+ cmdprio_bssplit=blocksize/percentage/class/level:blocksize/percentage/class/level
+
+ In this case, the priority class and priority level is defined inside
+ each entry. In comparison with the first accepted format, the second
+ accepted format does not restrict all entries to have the same priority
+ class and priority level.
+
+ For both formats, only the read and write data directions are supported,
+ values for trim IOs are ignored. This option is mutually exclusive with
+ the :option:`cmdprio_percentage` option.
.. option:: fixedbufs : [io_uring]
Split the load into cycles of the given time. In microseconds.
+.. option:: cpumode=str : [cpuio]
+
+ Specify how to stress the CPU. It can take these two values:
+
+ **noop**
+ This is the default where the CPU executes noop instructions.
+ **qsort**
+ Replace the default noop instructions loop with a qsort algorithm to
+ consume more energy.
+
.. option:: exit_on_io_done=bool : [cpuio]
Detect when I/O threads are done, then exit.
**write**
This is the default where write opcodes are issued as usual.
- **verify**
+ **write_and_verify**
Issue WRITE AND VERIFY commands. The BYTCHK bit is set to 0. This
directs the device to carry out a medium verification with no data
comparison. The writefua option is ignored with this selection.
- **same**
+ **verify**
+ This option is deprecated. Use write_and_verify instead.
+ **write_same**
Issue WRITE SAME commands. This transfers a single block to the device
and writes this same block of data to a contiguous sequence of LBAs
beginning at the specified offset. fio's block size parameter specifies
for each command but only the first 512 bytes will be used and
transferred to the device. The writefua option is ignored with this
selection.
+ **same**
+ This option is deprecated. Use write_same instead.
+ **write_same_ndob**
+ Issue WRITE SAME(16) commands as above but with the No Data Output
+ Buffer (NDOB) bit set. No data will be transferred to the device with
+ this bit set. Data written will be a pre-determined pattern such as
+ all zeroes.
+ **write_stream**
+ Issue WRITE STREAM(16) commands. Use the **stream_id** option to specify
+ the stream identifier.
+ **verify_bytchk_00**
+ Issue VERIFY commands with BYTCHK set to 00. This directs the
+ device to carry out a medium verification with no data comparison.
+ **verify_bytchk_01**
+ Issue VERIFY commands with BYTCHK set to 01. This directs the device to
+ compare the data on the device with the data transferred to the device.
+ **verify_bytchk_11**
+ Issue VERIFY commands with BYTCHK set to 11. This transfers a
+ single block to the device and compares the contents of this block with the
+ data on the device beginning at the specified offset. fio's block size
+ parameter specifies the total amount of data compared with this command.
+ However, only one block (sector) worth of data is transferred to the device.
+ This is similar to the WRITE SAME command except that data is compared instead
+ of written.
+
+.. option:: stream_id=int : [sg]
+
+ Set the stream identifier for WRITE STREAM commands. If this is set to 0 (which is not
+ a valid stream identifier) fio will open a stream and then close it when done. Default
+ is 0.
.. option:: hipri : [sg]
Specify the time between the SIGTERM and SIGKILL signals. Default is 1 second.
-.. option:: std_redirect=boot : [exec]
+.. option:: std_redirect=bool : [exec]
If set, stdout and stderr streams are redirected to files named from the job name. Default is true.
Stall the job for the specified period of time after an I/O has completed before issuing the
next. May be used to simulate processing being done by an application.
When the unit is omitted, the value is interpreted in microseconds. See
- :option:`thinktime_blocks` and :option:`thinktime_spin`.
+ :option:`thinktime_blocks`, :option:`thinktime_iotime` and :option:`thinktime_spin`.
.. option:: thinktime_spin=time
:option:`thinktime_blocks` blocks. If this is set to `issue`, then the trigger happens
at the issue side.
+.. option:: thinktime_iotime=time
+
+ Only valid if :option:`thinktime` is set - control :option:`thinktime`
+ interval by time. The :option:`thinktime` stall is repeated after IOs
+ are executed for :option:`thinktime_iotime`. For example,
+ ``--thinktime_iotime=9s --thinktime=1s`` repeat 10-second cycle with IOs
+ for 9 seconds and stall for 1 second. When the unit is omitted,
+ :option:`thinktime_iotime` is interpreted as a number of seconds. If
+ this option is used together with :option:`thinktime_blocks`, the
+ :option:`thinktime` stall is repeated after :option:`thinktime_iotime`
+ or after :option:`thinktime_blocks` IOs, whichever happens first.
+
.. option:: rate=int[,int][,int]
Cap the bandwidth used by this job. The number is in bytes/sec, the normal
between 0 and 7, with 0 being the highest. See man
:manpage:`ionice(1)`. Refer to an appropriate manpage for other operating
systems since meaning of priority may differ. For per-command priority
- setting, see I/O engine specific `cmdprio_percentage` and `hipri_percentage`
- options.
+ setting, see I/O engine specific :option:`cmdprio_percentage` and
+ :option:`cmdprio` options.
.. option:: prioclass=int
Set the I/O priority class. See man :manpage:`ionice(1)`. For per-command
- priority setting, see I/O engine specific `cmdprio_percentage` and
- `hipri_percentage` options.
+ priority setting, see I/O engine specific :option:`cmdprio_percentage`
+ and :option:`cmdprio_class` options.
.. option:: cpus_allowed=str
:option:`write_bw_log` for details about the filename format and `Log
File Formats`_ for how data is structured within the file.
+.. option:: log_entries=int
+
+ By default, fio will log an entry in the iops, latency, or bw log for
+ every I/O that completes. The initial number of I/O log entries is 1024.
+ When the log entries are all used, new log entries are dynamically
+ allocated. This dynamic log entry allocation may negatively impact
+ time-related statistics such as I/O tail latencies (e.g. 99.9th percentile
+ completion latency). This option allows specifying a larger initial
+ number of log entries to avoid run-time allocations of new log entries,
+ resulting in more precise time-related I/O statistics.
+ Also see :option:`log_avg_msec`. Defaults to 1024.
+
.. option:: log_avg_msec=int
By default, fio will log an entry in the iops, latency, or bw log for every
write_type_log for each log type, instead of the default zero-based
timestamps.
+.. option:: log_alternate_epoch=bool
+
+ If set, fio will log timestamps based on the epoch used by the clock specified
+ in the log_alternate_epoch_clock_id option, to the log files produced by
+ enabling write_type_log for each log type, instead of the default zero-based
+ timestamps.
+
+.. option:: log_alternate_epoch_clock_id=int
+
+ Specifies the clock_id to be used by clock_gettime to obtain the alternate epoch
+ if either log_unix_epoch or log_alternate_epoch are true. Otherwise has no
+ effect. Default value is 0, or CLOCK_REALTIME.
+
.. option:: block_error_percentiles=bool
If set, record errors in trim block-sized units from writes and trims and
projects / fio.git / blobdiff