calls will be excluded from other uses. Fio will manually clear it from the
CPU mask of other jobs.
+.. option:: job_start_clock_id=int
+ The clock_id passed to the call to `clock_gettime` used to record job_start
+ in the `json` output format. Default is 0, or CLOCK_REALTIME.
+
Target file/device
~~~~~~~~~~~~~~~~~~
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
+ Note: Windows and FreeBSD (refer to geom(4)) prevent write access to areas
of the disk containing in-use data (e.g. filesystems).
The filename "`-`" is a reserved name, meaning *stdin* or *stdout*. Which
reads and writes. See :manpage:`ionice(1)`. See also the
:option:`prioclass` option.
+.. option:: cmdprio_hint=int[,int] : [io_uring] [libaio]
+
+ Set the I/O priority hint 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 (no hint). A single value applies to reads and
+ writes. Comma-separated values may be specified for reads and writes.
+ See also the :option:`priohint` option.
+
.. option:: cmdprio=int[,int] : [io_uring] [libaio]
Set the I/O priority value to use for I/Os that must be issued with
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.
+ In this case, each entry will use the priority class, priority hint
+ and priority level defined by the options :option:`cmdprio_class`,
+ :option:`cmdprio` and :option:`cmdprio_hint` respectively.
The second accepted format for this option is:
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,
+ The third accepted format for this option is:
+
+ cmdprio_bssplit=blocksize/percentage/class/level/hint:...
+
+ This is an extension of the second accepted format that allows one to
+ also specify a priority hint.
+
+ 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 :option:`cmdprio_percentage` option.
want fio to use placement identifier only at indices 0, 2 and 5 specify
``fdp_pli=0,2,5``.
+.. option:: md_per_io_size=int : [io_uring_cmd] [xnvme]
+
+ Size in bytes for separate metadata buffer per IO. Default: 0.
+
+.. option:: pi_act=int : [io_uring_cmd]
+
+ Action to take when nvme namespace is formatted with protection
+ information. If this is set to 1 and namespace is formatted with
+ metadata size equal to protection information size, fio won't use
+ separate metadata buffer or extended logical block. If this is set to
+ 1 and namespace is formatted with metadata size greater than protection
+ information size, fio will not generate or verify the protection
+ information portion of metadata for write or read case respectively.
+ If this is set to 0, fio generates protection information for
+ write case and verifies for read case. Default: 1.
+
+ For 16 bit CRC generation fio will use isa-l if available otherwise
+ it will use the default slower generator.
+ (see: https://github.com/intel/isa-l)
+
+.. option:: pi_chk=str[,str][,str] : [io_uring_cmd]
+
+ Controls the protection information check. This can take one or more
+ of these values. Default: none.
+
+ **GUARD**
+ Enables protection information checking of guard field.
+ **REFTAG**
+ Enables protection information checking of logical block
+ reference tag field.
+ **APPTAG**
+ Enables protection information checking of application tag field.
+
+.. option:: apptag=int : [io_uring_cmd]
+
+ Specifies logical block application tag value, if namespace is
+ formatted to use end to end protection information. Default: 0x1234.
+
+.. option:: apptag_mask=int : [io_uring_cmd]
+
+ Specifies logical block application tag mask value, if namespace is
+ formatted to use end to end protection information. Default: 0xffff.
+
.. option:: cpuload=int : [cpuio]
Attempt to use the specified percentage of CPU cycles. This is a mandatory
User datagram protocol V6.
**unix**
UNIX domain socket.
+ **vsock**
+ VSOCK protocol.
- When the protocol is TCP or UDP, the port must also be given, as well as the
- hostname if the job is a TCP listener or UDP reader. For unix sockets, the
+ When the protocol is TCP, UDP or VSOCK, the port must also be given, as well as the
+ hostname if the job is a TCP or VSOCK listener or UDP reader. For unix sockets, the
normal :option:`filename` option should be used and the port is invalid.
+ When the protocol is VSOCK, the :option:`hostname` is the CID of the remote VM.
.. option:: listen : [netsplice] [net]
**hugepage**
Use hugepages, instead of existing posix memory backend. The
memory backend uses hugetlbfs. This require users to allocate
- hugepages, mount hugetlbfs and set an enviornment variable for
+ hugepages, mount hugetlbfs and set an environment variable for
XNVME_HUGETLB_PATH.
**spdk**
Uses SPDK's memory allocator.
creating but before connecting the libblkio instance. Each property must
have the format ``<name>=<value>``. Colons can be escaped as ``\:``.
These are set after the engine sets any other properties, so those can
- be overriden. Available properties depend on the libblkio version in use
+ be overridden. Available properties depend on the libblkio version in use
and are listed at
https://libblkio.gitlab.io/libblkio/blkio.html#properties
connecting but before starting the libblkio instance. Each property must
have the format ``<name>=<value>``. Colons can be escaped as ``\:``.
These are set after the engine sets any other properties, so those can
- be overriden. Available properties depend on the libblkio version in use
+ be overridden. Available properties depend on the libblkio version in use
and are listed at
https://libblkio.gitlab.io/libblkio/blkio.html#properties
I/O rate
~~~~~~~~
+.. option:: thinkcycles=int
+
+ Stall the job for the specified number of cycles after an I/O has completed before
+ issuing the next. May be used to simulate processing being done by an application.
+ This is not taken into account for the time to be waited on for :option:`thinktime`.
+ Might not have any effect on some platforms, this can be checked by trying a setting
+ a high enough amount of thinkcycles.
+
.. option:: thinktime=time
Stall the job for the specified period of time after an I/O has completed before issuing the
priority setting, see I/O engine specific :option:`cmdprio_percentage`
and :option:`cmdprio_class` options.
+.. option:: priohint=int
+
+ 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
+ :option:`cmdprio_hint` option.
+
.. option:: cpus_allowed=str
Controls the same options as :option:`cpumask`, but accepts a textual
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. 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
+ ``exit_what`` allows one 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:: per_job_logs=bool
- If set, this generates bw/clat/iops log with per file private filenames. If
- not set, jobs with identical names will share the log filename. Default:
- true.
+ If set to true, fio generates bw/clat/iops logs with per job unique
+ filenames. If set to false, jobs with identical names will share a log
+ filename. Note that when this option is set to false log files will be
+ opened in append mode and if log files already exist the previous
+ contents will not be overwritten. Default: true.
.. option:: group_reporting
same reporting group, unless if separated by a :option:`stonewall`, or by
using :option:`new_group`.
+ NOTE: When :option:`group_reporting` is used along with `json` output,
+ there are certain per-job properties which can be different between jobs
+ but do not have a natural group-level equivalent. Examples include
+ `kb_base`, `unit_base`, `sig_figs`, `thread_number`, `pid`, and
+ `job_start`. For these properties, the values for the first job are
+ recorded for the group.
+
.. option:: new_group
Start a new reporting group. See: :option:`group_reporting`. If not given,
.. option:: log_avg_msec=int
- By default, fio will log an entry in the iops, latency, or bw log for every
- I/O 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
- :option:`log_max_value` as well. Defaults to 0, logging all entries.
- Also see `Log File Formats`_.
+ By default, fio will log an entry in the iops, latency, or bw log for
+ every I/O that completes. When writing to the disk log, that can
+ quickly grow to a very large size. Setting this option directs fio to
+ instead record an average over the specified duration for each log
+ entry, reducing the resolution of the log. When the job completes, fio
+ will flush any accumulated latency log data, so the final log interval
+ may not match the value specified by this option and there may even be
+ duplicate timestamps. See :option:`log_window_value` as well. Defaults
+ to 0, logging entries for each I/O. Also see `Log File Formats`_.
.. option:: log_hist_msec=int
histogram logs contain 1216 latency bins. See :option:`write_hist_log`
and `Log File Formats`_.
-.. option:: log_max_value=bool
+.. option:: log_window_value=str, log_max_value=str
- If :option:`log_avg_msec` 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.
+ If :option:`log_avg_msec` is set, fio by default logs the average over that
+ window. This option determines whether fio logs the average, maximum or
+ both the values over the window. This only affects the latency logging,
+ as both average and maximum values for iops or bw log will be same.
+ Accepted values are:
+
+ **avg**
+ Log average value over the window. The default.
+
+ **max**
+ Log maximum value in the window.
+
+ **both**
+ Log both average and maximum value over the window.
+
+ **0**
+ Backward-compatible alias for **avg**.
+
+ **1**
+ Backward-compatible alias for **max**.
.. option:: log_offset=bool
.. option:: log_unix_epoch=bool
- If set, fio will log Unix timestamps to the log files produced by enabling
- write_type_log for each log type, instead of the default zero-based
- timestamps.
+ Backwards compatible alias for log_alternate_epoch.
.. option:: log_alternate_epoch=bool
.. 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.
+ Specifies the clock_id to be used by clock_gettime to obtain the alternate
+ epoch if log_alternate_epoch is true. Otherwise has no effect. Default
+ value is 0, or CLOCK_REALTIME.
.. option:: block_error_percentiles=bool
by the ioengine specific :option:`cmdprio_percentage`.
Fio defaults to logging every individual I/O but when windowed logging is set
-through :option:`log_avg_msec`, either the average (by default) or the maximum
-(:option:`log_max_value` is set) *value* seen over the specified period of time
-is recorded. Each *data direction* seen within the window period will aggregate
-its values in a separate row. Further, when using windowed logging the *block
-size* and *offset* entries will always contain 0.
+through :option:`log_avg_msec`, either the average (by default), the maximum
+(:option:`log_window_value` is set to max) *value* seen over the specified period
+of time, or both the average *value* and maximum *value1* (:option:`log_window_value`
+is set to both) is recorded. The log file format when both the values are reported
+takes this form:
+
+ *time* (`msec`), *value*, *value1*, *data direction*, *block size* (`bytes`),
+ *offset* (`bytes`), *command priority*
+
+
+Each *data direction* seen within the window period will aggregate its values in a
+separate row. Further, when using windowed logging the *block size* and *offset*
+entries will always contain 0.
Client/Server
server. The `server` string follows the same format as it does on the server
side, to allow IP/hostname/socket and port strings.
+Note that all job options must be defined in job files when running fio as a
+client. Any job options specified in `remote-args` will be ignored.
+
Fio can connect to multiple servers this way::
fio --client=<server1> <job file(s)> --client=<server2> <job file(s)>
projects / fio.git / blobdiff