Dump info related to I/O rate switching.
*compress*
Dump info related to log compress/decompress.
+ *steadystate*
+ Dump info related to steadystate detection.
+ *helperthread*
+ Dump info related to the helper thread.
+ *zbd*
+ Dump info related to support for zoned block devices.
*?* or *help*
Show available debug options.
.. option:: --alloc-size=kb
- Set the internal smalloc pool size to `kb` in KiB. The
- ``--alloc-size`` switch allows one to use a larger pool size for smalloc.
+ Allocate additional internal smalloc pools of size `kb` in KiB. The
+ ``--alloc-size`` option increases shared memory set aside for use by fio.
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.
Pre-allocate via :manpage:`fallocate(2)` with
FALLOC_FL_KEEP_SIZE set.
+ **truncate**
+ Extend file to final size via :manpage:`ftruncate(2)`
+ instead of allocating.
+
**0**
Backward-compatible alias for **none**.
May not be available on all supported platforms. **keep** is only available
on Linux. If using ZFS on Solaris this cannot be set to **posix**
because ZFS doesn't support pre-allocation. Default: **native** if any
- pre-allocation methods are available, **none** if not.
+ pre-allocation methods except **truncate** are available, **none** if not.
+
+ Note that using **truncate** on Windows will interact surprisingly
+ with non-sequential write patterns. When writing to a file that has
+ been extended by setting the end-of-file information, Windows will
+ backfill the unwritten portion of the file up to that offset with
+ zeroes before issuing the new write. This means that a single small
+ write to the end of an extended file will stall until the entire
+ file has been filled with zeroes.
.. option:: fadvise_hint=str
is incremented for each sub-job (i.e. when :option:`numjobs` option is
specified). This option is useful if there are several jobs which are
intended to operate on a file in parallel disjoint segments, with even
- spacing between the starting points.
+ spacing between the starting points. Percentages can be used for this option.
+ If a percentage is given, the generated offset will be aligned to the minimum
+ ``blocksize`` or to the value of ``offset_align`` if provided.
.. option:: number_ios=int
.. option:: fdatasync=int
Like :option:`fsync` but uses :manpage:`fdatasync(2)` to only sync data and
- not metadata blocks. In Windows, FreeBSD, and DragonFlyBSD there is no
+ not metadata blocks. In Windows, FreeBSD, 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.
**pvsync2**
Basic :manpage:`preadv2(2)` or :manpage:`pwritev2(2)` I/O.
+ **io_uring**
+ Fast Linux native asynchronous I/O. Supports async IO
+ for both direct and buffered IO.
+ This engine defines engine specific options.
+
**libaio**
Linux native asynchronous I/O. Note that Linux may only support
queued behavior with non-buffered I/O (set ``direct=1`` or
Asynchronous read and write using DDN's Infinite Memory Engine (IME).
This engine will try to stack as much IOs as possible by creating
requests for IME. FIO will then decide when to commit these requests.
+ **libiscsi**
+ Read and write iscsi lun with libiscsi.
+ **nbd**
+ Read and write a Network Block Device (NBD).
I/O engine specific parameters
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
with the caveat that when used on the command line, they must come after the
:option:`ioengine` that defines them is selected.
+.. option:: hipri : [io_uring]
+
+ If this option is set, fio will attempt to use polled IO completions.
+ Normal IO completions generate interrupts to signal the completion of
+ IO, polled completions do not. Hence they are require active reaping
+ by the application. The benefits are more efficient IO for high IOPS
+ scenarios, and lower latencies for low queue depth IO.
+
+.. option:: fixedbufs : [io_uring]
+
+ If fio is asked to do direct IO, then Linux will map pages for each
+ IO call, and release them when IO is done. If this option is set, the
+ pages are pre-mapped before IO is started. This eliminates the need to
+ map and release for each IO. This is more efficient, and reduces the
+ IO latency as well.
+
+.. option:: registerfiles : [io_uring]
+ With this option, fio registers the set of files being used with the
+ kernel. This avoids the overhead of managing file counts in the kernel,
+ making the submission and completion part more lightweight. Required
+ for the below :option:`sqthread_poll` option.
+
+.. option:: sqthread_poll : [io_uring]
+
+ Normally fio will submit IO by issuing a system call to notify the
+ kernel of available items in the SQ ring. If this option is set, the
+ act of submitting IO will be done by a polling thread in the kernel.
+ This frees up cycles for fio, at the cost of using more CPU in the
+ system.
+
+.. option:: sqthread_poll_cpu : [io_uring]
+
+ When :option:`sqthread_poll` is set, this option provides a way to
+ define which CPU should be used for the polling thread.
+
.. option:: userspace_reap : [libaio]
Normally, with the libaio engine in use, fio will use the
turns on verbose logging from libcurl, 2 additionally enables
HTTP IO tracing. Default is **0**
+.. option:: uri=str : [nbd]
+
+ Specify the NBD URI of the server to test. The string
+ is a standard NBD URI
+ (see https://github.com/NetworkBlockDevice/nbd/tree/master/doc).
+ Example URIs: nbd://localhost:10809
+ nbd+unix:///?socket=/tmp/socket
+ nbds://tlshost/exportname
+
I/O depth
~~~~~~~~~
this option can reduce both performance and the :option:`iodepth` achieved.
This option only applies to I/Os issued for a single job except when it is
- enabled along with :option:`io_submit_mode`=offload. In offload mode, fio
+ enabled along with :option:`io_submit_mode`\=offload. In offload mode, fio
will check for overlap among all I/Os submitted by offload jobs with :option:`serialize_overlap`
- enabled. Threads must be used for all such jobs.
+ enabled.
Default: false.
Each job will get a unique CPU from the CPU set.
**shared** is the default behavior, if the option isn't specified. If
- **split** is specified, then fio will will assign one cpu per job. If not
+ **split** is specified, then fio will assign one cpu per job. If not
enough CPUs are given for the jobs listed, then fio will roundrobin the CPUs
in the set.
.. option:: exitall
- By default, fio will continue running all other jobs when one job finishes
- but sometimes this is not the desired action. Setting ``exitall`` will
- instead make fio terminate all other jobs when one job finishes.
+ By default, fio will continue running all other jobs when one job finishes.
+ Sometimes this is not the desired action. Setting ``exitall`` will instead
+ make fio terminate all jobs in the same group, as soon as one job of that
+ group finishes.
+
+.. option:: exit_what
+
+ By default, fio will continue running all other jobs when one job finishes.
+ Sometimes this is not the desired action. Setting ``exit_all`` will
+ instead make fio terminate all jobs in the same group. The option
+ ``exit_what`` allows to control which jobs get terminated when ``exitall`` is
+ enabled. The default is ``group`` and does not change the behaviour of
+ ``exitall``. The setting ``all`` terminates all jobs. The setting ``stonewall``
+ terminates all currently running jobs across all groups and continues execution
+ with the next stonewalled group.
.. option:: exec_prerun=str
2;card0;0;0;7139336;121836;60004;1;10109;27.932460;116.933948;220;126861;3495.446807;1085.368601;226;126864;3523.635629;1089.012448;24063;99944;50.275485%;59818.274627;5540.657370;7155060;122104;60004;1;8338;29.086342;117.839068;388;128077;5032.488518;1234.785715;391;128085;5061.839412;1236.909129;23436;100928;50.287926%;59964.832030;5644.844189;14.595833%;19.394167%;123706;0;7313;0.1%;0.1%;0.1%;0.1%;0.1%;0.1%;100.0%;0.00%;0.00%;0.00%;0.00%;0.00%;0.00%;0.01%;0.02%;0.05%;0.16%;6.04%;40.40%;52.68%;0.64%;0.01%;0.00%;0.01%;0.00%;0.00%;0.00%;0.00%;0.00%
A description of this job goes here.
-The job description (if provided) follows on a second line.
+The job description (if provided) follows on a second line for terse v2.
+It appears on the same line for other terse versions.
To enable terse output, use the :option:`--minimal` or
:option:`--output-format`\=terse command line options. The
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_min;read_clat_max;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_min;write_clat_max;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;cpu_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
+In client/server mode terse output differs from what appears when jobs are run
+locally. Disk utilization data is omitted from the standard terse output and
+for v3 and later appears on its own separate line at the end of each terse
+reporting cycle.
+
JSON output
------------
its values in a separate row. Further, when using windowed logging the *block
size* and *offset* entries will always contain 0.
+
Client/Server
-------------
/mnt/nfs/fio/192.168.10.120.fileio.tmp
/mnt/nfs/fio/192.168.10.121.fileio.tmp
+
+Terse output in client/server mode will differ slightly from what is produced
+when fio is run in stand-alone mode. See the terse output section for details.
projects / fio.git / blobdiff