If the option accepts an upper and lower range, use a colon ':' or
minus '-' to separate such values. See :ref:`irange <irange>`.
+ If the lower value specified happens to be larger than the upper value,
+ two values are swapped.
.. _bool:
.. option:: numjobs=int
- Create the specified number of clones of this job. May be used to setup a
+ Create the specified number of clones of this job. Each clone of job
+ is spawned as an independent thread or process. May be used to setup a
larger number of threads/processes doing the same thing. Each thread is
reported separately; to see statistics for all clones as a whole, use
:option:`group_reporting` in conjunction with :option:`new_group`.
.. option:: runtime=time
- Tell fio to terminate processing after the specified number of seconds. It
+ Tell fio to terminate processing after the specified period of time. It
can be quite hard to determine for how long a specified job will run, so
- this parameter is handy to cap the total runtime to a given time.
+ this parameter is handy to cap the total runtime to a given time. When
+ the unit is omitted, the value is given in seconds.
.. option:: time_based
before logging results, thus minimizing the runtime required for stable
results. Note that the ``ramp_time`` is considered lead in time for a job,
thus it will increase the total runtime if a special timeout or
- :option:`runtime` is specified.
+ :option:`runtime` is specified. When the unit is omitted, the value is
+ given in seconds.
.. option:: clocksource=str
.. option:: gtod_reduce=bool
Enable all of the :manpage:`gettimeofday(2)` reducing options
- (:option:`disable_clat`, :option:`disable_slat`, :option:`disable_bw`) plus
+ (:option:`disable_clat`, :option:`disable_slat`, :option:`disable_bw_measurement`) plus
reduce precision of the timeout somewhat to really shrink the
:manpage:`gettimeofday(2)` call count. With this option enabled, we only do
about 0.4% of the :manpage:`gettimeofday(2)` calls we would have done if all
Fio normally makes up a `filename` based on the job name, thread number, and
file number. If you want to share files between threads in a job or several
- jobs, specify a `filename` for each of them to override the default. If the
- ioengine is file based, you can specify a number of files by separating the
- names with a ':' colon. So if you wanted a job to open :file:`/dev/sda` and
- :file:`/dev/sdb` as the two working files, you would use
- ``filename=/dev/sda:/dev/sdb``.
+ jobs with fixed file paths, specify a `filename` for each of them to override
+ the default. If the ioengine is file based, you can specify a number of files
+ by separating the names with a ':' colon. So if you wanted a job to open
+ :file:`/dev/sda` and :file:`/dev/sdb` as the two working files, you would use
+ ``filename=/dev/sda:/dev/sdb``. This also means that whenever this option is
+ specified, :option:`nrfiles` is ignored. The size of regular files specified
+ by this option will be :option:`size` divided by number of files unless
+ explicit size is specified by :option:`filesize`.
+
On Windows, disk devices are accessed as :file:`\\\\.\\PhysicalDrive0` for
the first device, :file:`\\\\.\\PhysicalDrive1` for the second etc.
Note: Windows and FreeBSD prevent write access to areas
.. option:: nrfiles=int
- Number of files to use for this job. Defaults to 1.
+ Number of files to use for this job. Defaults to 1. The size of files
+ will be :option:`size` divided by this unless explicit size is specified by
+ :option:`filesize`. Files are created for each thread separately, and each
+ file will have a file number within its name by default, as explained in
+ :option:`filename` section.
+
.. option:: openfiles=int
If this isn't set, fio will abort jobs that are destructive (e.g. that write)
to what appears to be a mounted device or partition. This should help catch
creating inadvertently destructive tests, not realizing that the test will
- destroy data on the mounted file system. Default: false.
+ destroy data on the mounted file system. Note that some platforms don't allow
+ writing against a mounted device regardless of this option. Default: false.
.. option:: pre_read=bool
.. option:: offset=int
- Start I/O at the given offset in the file. The data before the given offset
- will not be touched. This effectively caps the file size at `real_size -
- offset`.
+ 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 ``blockalign``-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
+ :option:`size` to constrain the start and end range of the I/O workload.
.. option:: offset_increment=int
blocks given. For example, if you give 32 as a parameter, fio will sync the
file for every 32 writes issued. If fio is using non-buffered I/O, we may
not sync the file. The exception is the sg I/O engine, which synchronizes
- the disk cache anyway.
+ the disk cache anyway. Defaults to 0, which means no sync every certain
+ number of writes.
.. option:: fdatasync=int
Like :option:`fsync` but uses :manpage:`fdatasync(2)` to only sync data and
- not metadata blocks. In FreeBSD and Windows there is no
+ not metadata blocks. In Windows, FreeBSD, and DragonFlyBSD there is no
:manpage:`fdatasync(2)`, this falls back to using :manpage:`fsync(2)`.
+ Defaults to 0, which means no sync data every certain number of writes.
.. option:: write_barrier=int
.. option:: invalidate=bool
Invalidate the buffer/page cache parts for this file prior to starting
- I/O. Defaults to true.
+ I/O if the platform and file type support it. Defaults to true.
+ This will be ignored if :option:`pre_read` is also specified for the
+ same job.
.. option:: sync=bool
**mmapshared**
Same as mmap, but use a MMAP_SHARED mapping.
+ **cudamalloc**
+ Use GPU memory as the buffers for GPUDirect RDMA benchmark.
+
The area allocated is a function of the maximum allowed bs size for the job,
multiplied by the I/O depth given. Note that for **shmhuge** and
**mmaphuge** to work, the system must have free huge pages allocated. This
.. option:: size=int
- The total size of file I/O for this job. Fio will run until this many bytes
- has been transferred, unless runtime is limited by other options (such as
- :option:`runtime`, for instance, or increased/decreased by
- :option:`io_size`). Unless specific :option:`nrfiles` and :option:`filesize`
- options are given, fio will divide this size between the available files
- specified by the job. If not set, fio will use the full size of the given
+ The total size of file I/O for each thread of this job. Fio will run until
+ this many bytes has been transferred, unless runtime is limited by other options
+ (such as :option:`runtime`, for instance, or increased/decreased by :option:`io_size`).
+ Fio will divide this size between the available files determined by options
+ such as :option:`nrfiles`, :option:`filename`, unless :option:`filesize` is
+ specified by the job. If the result of division happens to be 0, the size is
+ set to the physical size of the given files or devices if they exist.
+ If this option is not specified, fio will use the full size of the given
files or devices. If the files do not exist, size must be given. It is also
possible to give size as a percentage between 1 and 100. If ``size=20%`` is
given, fio will use 20% of the full size of the given files or devices.
+ Can be combined with :option:`offset` to constrain the start and end range
+ that I/O will be done within.
.. option:: io_size=int, io_limit=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.
.. option:: file_append=bool
**sync**
Basic :manpage:`read(2)` or :manpage:`write(2)`
I/O. :manpage:`lseek(2)` is used to position the I/O location.
+ See :option:`fsync` and :option:`fdatasync` for syncing write I/Os.
**psync**
Basic :manpage:`pread(2)` or :manpage:`pwrite(2)` I/O. Default on
DDIR_TRIM
does fallocate(,mode = FALLOC_FL_KEEP_SIZE|FALLOC_FL_PUNCH_HOLE).
+ **ftruncate**
+ I/O engine that sends :manpage:`ftruncate(2)` operations in response
+ to write (DDIR_WRITE) events. Each ftruncate issued sets the file's
+ size to the current block offset. Block size is ignored.
+
**e4defrag**
I/O engine that does regular EXT4_IOC_MOVE_EXT ioctls to simulate
defragment activity in request to DDIR_WRITE event.
files based on the offset generated by fio backend. (see the example
job file to create such files, use ``rw=write`` option). Please
note, you might want to set necessary environment variables to work
- with hdfs/libhdfs properly. Each jobs uses it's own connection to
+ with hdfs/libhdfs properly. Each job uses its own connection to
HDFS.
**mtd**
reap events. The reaping mode is only enabled when polling for a minimum of
0 events (e.g. when :option:`iodepth_batch_complete` `=0`).
-.. option:: hipri : [psyncv2]
+.. option:: hipri : [pvsync2]
Set RWF_HIPRI on I/O, indicating to the kernel that it's of higher priority
than normal.
.. option:: cpuload=int : [cpuio]
- Attempt to use the specified percentage of CPU cycles.
+ Attempt to use the specified percentage of CPU cycles. This is a mandatory
+ option when using cpuio I/O engine.
.. option:: cpuchunks=int : [cpuio]
.. option:: thinktime=time
- Stall the job x microseconds after an I/O has completed before issuing the
- next. May be used to simulate processing being done by an application. See
+ 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 given in microseconds. See
:option:`thinktime_blocks` and :option:`thinktime_spin`.
.. option:: thinktime_spin=time
Only valid if :option:`thinktime` is set - pretend to spend CPU time doing
something with the data received, before falling back to sleeping for the
- rest of the period specified by :option:`thinktime`.
+ rest of the period specified by :option:`thinktime`. When the unit is
+ omitted, the value is given in microseconds.
.. option:: thinktime_blocks=int
.. option:: latency_target=time
If set, fio will attempt to find the max performance point that the given
- workload will run at while maintaining a latency below this target. The
- values is given in microseconds. See :option:`latency_window` and
- :option:`latency_percentile`.
+ workload will run at while maintaining a latency below this target. When
+ the unit is omitted, the value is given in microseconds. See
+ :option:`latency_window` and :option:`latency_percentile`.
.. option:: latency_window=time
Used with :option:`latency_target` to specify the sample window that the job
- is run at varying queue depths to test the performance. The value is given
- in microseconds.
+ is run at varying queue depths to test the performance. When the unit is
+ omitted, the value is given in microseconds.
.. option:: latency_percentile=float
.. option:: max_latency=time
- If set, fio will exit the job if it exceeds this maximum latency. It will
- exit with an ETIME error.
+ If set, fio will exit the job with an ETIMEDOUT error if it exceeds this
+ maximum latency. When the unit is omitted, the value is given in
+ microseconds.
.. option:: rate_cycle=int
.. option:: thread
Fio defaults to forking jobs, however if this option is given, fio will use
- :manpage:`pthread_create(3)` to create threads instead.
+ POSIX Threads function :manpage:`pthread_create(3)` to create threads instead
+ of forking processes.
.. option:: wait_for=str
**sha1**
Use optimized sha1 as the checksum function.
+ **sha3-224**
+ Use optimized sha3-224 as the checksum function.
+
+ **sha3-256**
+ Use optimized sha3-256 as the checksum function.
+
+ **sha3-384**
+ Use optimized sha3-384 as the checksum function.
+
+ **sha3-512**
+ Use optimized sha3-512 as the checksum function.
+
**meta**
This option is deprecated, since now meta information is included in
generic verification header and meta verification happens by
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.
+ which disables steady state detection. When the unit is omitted, the
+ value is given in seconds.
.. option:: steadystate_ramp_time=time, ss_ramp=time
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.
+ default is 0. When the unit is omitted, the value is given in seconds.
Measurements and reporting
all jobs in a file will be part of the same reporting group, unless
separated by a :option:`stonewall`.
+.. option:: stats
+
+ 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.
+
.. option:: write_bw_log=str
If given, write a bandwidth log for this job. Can be used to store data of
the number of calls to :manpage:`gettimeofday(2)`, as that does impact
performance at really high IOPS rates. Note that to really get rid of a
large amount of these calls, this option must be used with
- :option:`disable_slat` and :option:`disable_bw` as well.
+ :option:`disable_slat` and :option:`disable_bw_measurement` as well.
.. option:: disable_clat=bool
Disable measurements of submission latency numbers. See
:option:`disable_slat`.
-.. option:: disable_bw=bool
+.. option:: disable_bw_measurement=bool, disable_bw=bool
Disable measurements of throughput/bandwidth numbers. See
:option:`disable_lat`.
If set dump every error even if it is non fatal, true by default. If
disabled only fatal error will be dumped.
+Running predefined workloads
+----------------------------
+
+Fio includes predefined profiles that mimic the I/O workloads generated by
+other tools.
+
+.. option:: profile=str
+
+ The predefined workload to run. Current profiles are:
+
+ **tiobench**
+ Threaded I/O bench (tiotest/tiobench) like workload.
+
+ **act**
+ Aerospike Certification Tool (ACT) like workload.
+
+To view a profile's additional options use :option:`--cmdhelp` after specifying
+the profile. For example::
+
+$ fio --profile=act --cmdhelp
+
+Act profile options
+~~~~~~~~~~~~~~~~~~~
+
+.. option:: device-names=str
+ :noindex:
+
+ Devices to use.
+
+.. option:: load=int
+ :noindex:
+
+ ACT load multiplier. Default: 1.
+
+.. option:: test-duration=time
+ :noindex:
+
+ How long the entire test takes to run. Default: 24h.
+
+.. option:: threads-per-queue=int
+ :noindex:
+
+ Number of read IO threads per device. Default: 8.
+
+.. option:: read-req-num-512-blocks=int
+ :noindex:
+
+ Number of 512B blocks to read at the time. Default: 3.
+
+.. option:: large-block-op-kbytes=int
+ :noindex:
+
+ Size of large block ops in KiB (writes). Default: 131072.
+
+.. option:: prep
+ :noindex:
+
+ Set to run ACT prep phase.
+
+Tiobench profile options
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. option:: size=str
+ :noindex:
+
+ Size in MiB
+
+.. option:: block=int
+ :noindex:
+
+ Block size in bytes. Default: 4096.
+
+.. option:: numruns=int
+ :noindex:
+
+ Number of runs.
+
+.. option:: dir=str
+ :noindex:
+
+ Test directory.
+
+.. option:: threads=int
+ :noindex:
+
+ Number of threads.
Interpreting the output
-----------------------
Fio spits out a lot of output. While running, fio will display the status of the
jobs created. An example of that would be::
- Jobs: 1: [_r] [24.8% done] [r=20992KiB/s,w=24064KiB/s,t=0KiB/s] [r=82,w=94,t=0 iops] [eta 00h:01m:31s]
+ Jobs: 1 (f=1): [_(1),M(1)][24.8%][r=20.5MiB/s,w=23.5MiB/s][r=82,w=94 IOPS][eta 01m:31s]
The characters inside the square brackets denote the current status of each
thread. The possible values (in typical life cycle order) are:
line as is needed. For instance, if you have 10 readers and 10 writers running,
the output would look like this::
- Jobs: 20 (f=20): [R(10),W(10)] [4.0% done] [r=20992KiB/s,w=24064KiB/s,t=0KiB/s] [r=82,w=94,t=0 iops] [eta 57m:36s]
+ Jobs: 20 (f=20): [R(10),W(10)][4.0%][r=20.5MiB/s,w=23.5MiB/s][r=82,w=94 IOPS][eta 57m:36s]
Fio will still maintain the ordering, though. So the above means that jobs 1..10
are readers, and 11..20 are writers.
The other values are fairly self explanatory -- number of threads currently
-running and doing I/O, rate of I/O since last check (read speed listed first,
-then write speed), and the estimated completion percentage and time for the
+running and doing I/O, the number of currently open files (f=), the rate of I/O
+since last check (read speed listed first, then write speed and optionally trim
+speed), and the estimated completion percentage and time for the current
running group. It's impossible to estimate runtime of the following groups (if
any). Note that the string is displayed in order, so it's possible to tell which
of the jobs are currently doing what. The first character is the first job
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