.PD
.RE
.P
+For Zone Block Device Mode:
+.RS
+.P
+.PD 0
+z means Zone
+.P
+.PD
+.RE
+.P
With `kb_base=1024' (the default), the unit prefixes are opposite
from those specified in the SI and IEC 80000-13 standards to provide
compatibility with old scripts. For example, 4k means 4096.
.PD
.RE
.P
+`z' suffix specifies that the value is measured in zones.
+Value is recalculated once block device's zone size becomes known.
+.P
If the option accepts an upper and lower range, use a colon ':' or
minus '\-' to separate such values. See \fIirange\fR parameter type.
If the lower value specified happens to be larger than the upper value
.B $jobname
The name of the worker thread or process.
.TP
+.B $clientuid
+IP of the fio process when using client/server mode.
+.TP
.B $jobnum
The incremental number of the worker thread or process.
.TP
.TP
.BI ioscheduler \fR=\fPstr
Attempt to switch the device hosting the file to the specified I/O scheduler
-before running.
+before running. If the file is a pipe, a character device file or if device
+hosting the file could not be determined, this option is ignored.
.TP
.BI create_serialize \fR=\fPbool
If true, serialize the file creation for the jobs. This may be handy to
Zoned block device mode. I/O happens sequentially in each zone, even if random
I/O has been selected. Random I/O happens across all zones instead of being
restricted to a single zone.
+Trim is handled using a zone reset operation. Trim only considers non-empty
+sequential write required and sequential write preferred zones.
.RE
.RE
.TP
block device, the zone capacity is obtained from the device information and this
option is ignored.
.TP
-.BI zoneskip \fR=\fPint
+.BI zoneskip \fR=\fPint[z]
For \fBzonemode\fR=strided, the number of bytes to skip after \fBzonesize\fR
bytes of data have been transferred.
.BI job_max_open_zones \fR=\fPint
Limit on the number of simultaneously opened zones per single thread/process.
.TP
+.BI ignore_zone_limits \fR=\fPbool
+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 \fBmax_open_zones\fR
+value to be larger than the device reported limit. Default: false.
+.TP
.BI zone_reset_threshold \fR=\fPfloat
A number between zero and one that indicates the ratio of logical blocks with
data to the total number of logical blocks in the test above which zones
times before generating a new offset.
.RE
.TP
-.BI unified_rw_reporting \fR=\fPbool
+.BI unified_rw_reporting \fR=\fPstr
Fio normally reports statistics on a per data direction basis, meaning that
-reads, writes, and trims are accounted and reported separately. If this
-option is set fio sums the results and report them as "mixed" instead.
+reads, writes, and trims are accounted and reported separately. This option
+determines whether fio reports the results normally, summed together, or as
+both options.
+Accepted values are:
+.RS
+.TP
+.B none
+Normal statistics reporting.
+.TP
+.B mixed
+Statistics are summed per data direction and reported together.
+.TP
+.B both
+Statistics are reported normally, followed by the mixed statistics.
+.TP
+.B 0
+Backward-compatible alias for \fBnone\fR.
+.TP
+.B 1
+Backward-compatible alias for \fBmixed\fR.
+.TP
+.B 2
+Alias for \fBboth\fR.
+.RE
.TP
.BI randrepeat \fR=\fPbool
Seed the random number generator used for random I/O patterns in a
should be associated with them.
.RE
.TP
-.BI offset \fR=\fPint
+.BI offset \fR=\fPint[%|z]
Start I/O at the provided offset in the file, given as either a fixed size in
-bytes or a percentage. If a percentage is given, the generated offset will be
+bytes, zones or a percentage. If a percentage is given, the generated offset will be
aligned to the minimum \fBblocksize\fR or to the value of \fBoffset_align\fR if
provided. Data before the given offset will not be touched. This
effectively caps the file size at `real_size \- offset'. Can be combined with
\fBsize\fR to constrain the start and end range of the I/O workload.
A percentage can be specified by a number between 1 and 100 followed by '%',
-for example, `offset=20%' to specify 20%.
+for example, `offset=20%' to specify 20%. In ZBD mode, value can be set as
+number of zones using 'z'.
.TP
.BI offset_align \fR=\fPint
If set to non-zero value, the byte offset generated by a percentage \fBoffset\fR
is aligned upwards to this value. Defaults to 0 meaning that a percentage
offset is aligned to the minimum block size.
.TP
-.BI offset_increment \fR=\fPint
+.BI offset_increment \fR=\fPint[%|z]
If this is provided, then the real offset becomes `\fBoffset\fR + \fBoffset_increment\fR
* thread_number', where the thread number is a counter that starts at 0 and
is incremented for each sub-job (i.e. when \fBnumjobs\fR option is
intended to operate on a file in parallel disjoint segments, with even
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
-\fBblocksize\fR or to the value of \fBoffset_align\fR if provided.
+\fBblocksize\fR or to the value of \fBoffset_align\fR if provided.In ZBD mode, value
+can be set as number of zones using 'z'.
.TP
.BI number_ios \fR=\fPint
Fio will normally perform I/Os until it has exhausted the size of the region
limit reads or writes to a certain rate. If that is the case, then the
distribution may be skewed. Default: 50.
.TP
-.BI random_distribution \fR=\fPstr:float[,str:float][,str:float]
+.BI random_distribution \fR=\fPstr:float[:float][,str:float][,str:float]
By default, fio will use a completely uniform random distribution when asked
to perform random I/O. Sometimes it is useful to skew the distribution in
specific ways, ensuring that some parts of the data is more hot than others.
map. For the \fBnormal\fR distribution, a normal (Gaussian) deviation is
supplied as a value between 0 and 100.
.P
+The second, optional float is allowed for \fBpareto\fR, \fBzipf\fR and \fBnormal\fR
+distributions. It allows to set base of distribution in non-default place, giving
+more control over most probable outcome. This value is in range [0-1] which maps linearly to
+range of possible random values.
+Defaults are: random for \fBpareto\fR and \fBzipf\fR, and 0.5 for \fBnormal\fR.
+If you wanted to use \fBzipf\fR with a `theta` of 1.2 centered on 1/4 of allowed value range,
+you would use `random_distibution=zipf:1.2:0.25`.
+.P
For a \fBzoned\fR distribution, fio supports specifying percentages of I/O
access that should fall within what range of the file or device. For
example, given a criteria of:
this option will also enable \fBrefill_buffers\fR to prevent every buffer
being identical.
.TP
+.BI dedupe_mode \fR=\fPstr
+If \fBdedupe_percentage\fR is given, then this option controls how fio
+generates the dedupe buffers.
+.RS
+.RS
+.TP
+.B repeat
+.P
+.RS
+Generate dedupe buffers by repeating previous writes
+.RE
+.TP
+.B working_set
+.P
+.RS
+Generate dedupe buffers from working set
+.RE
+.RE
+.P
+\fBrepeat\fR is the default option for fio. Dedupe buffers are generated
+by repeating previous unique write.
+
+\fBworking_set\fR is a more realistic workload.
+With \fBworking_set\fR, \fBdedupe_working_set_percentage\fR should be provided.
+Given that, fio will use the initial unique write buffers as its working set.
+Upon deciding to dedupe, fio will randomly choose a buffer from the working set.
+Note that by using \fBworking_set\fR the dedupe percentage will converge
+to the desired over time while \fBrepeat\fR maintains the desired percentage
+throughout the job.
+.RE
+.RE
+.TP
+.BI dedupe_working_set_percentage \fR=\fPint
+If \fBdedupe_mode\fR is set to \fBworking_set\fR, then this controls
+the percentage of size of the file or device used as the buffers
+fio will choose to generate the dedupe buffers from
+.P
+.RS
+Note that \fBsize\fR needs to be explicitly provided and only 1 file
+per job is supported
+.RE
+.TP
.BI invalidate \fR=\fPbool
Invalidate the buffer/page cache parts of the files to be used prior to
starting I/O if the platform and file type support it. Defaults to true.
simulate a smaller amount of memory. The amount specified is per worker.
.SS "I/O size"
.TP
-.BI size \fR=\fPint
+.BI size \fR=\fPint[%|z]
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 \fBruntime\fR, for instance, or increased/decreased by \fBio_size\fR).
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 \fBoffset\fR to constrain the start and end range
-that I/O will be done within.
+given, fio will use 20% of the full size of the given files or devices. In ZBD mode,
+size can be given in units of number of zones using 'z'. Can be combined with \fBoffset\fR to
+constrain the start and end range that I/O will be done within.
.TP
-.BI io_size \fR=\fPint "\fR,\fB io_limit" \fR=\fPint
+.BI io_size \fR=\fPint[%|z] "\fR,\fB io_limit" \fR=\fPint[%|z]
Normally fio operates within the region set by \fBsize\fR, which means
that the \fBsize\fR option sets both the region and size of I/O to be
performed. Sometimes that is not what you want. With this option, it is
done. The opposite is also possible \-\- if \fBsize\fR is set to 20GiB,
and \fBio_size\fR is set to 40GiB, then fio will do 40GiB of I/O within
the 0..20GiB region. Value can be set as percentage: \fBio_size\fR=N%.
-In this case \fBio_size\fR multiplies \fBsize\fR= value.
+In this case \fBio_size\fR multiplies \fBsize\fR= value. In ZBD mode, value can
+also be set as number of zones using 'z'.
.TP
.BI filesize \fR=\fPirange(int)
Individual file sizes. May be a range, in which case fio will select sizes
.TP
.BI fill_device \fR=\fPbool "\fR,\fB fill_fs" \fR=\fPbool
Sets size to something really large and waits for ENOSPC (no space left on
-device) as the terminating condition. Only makes sense with sequential
+device) or EDQUOT (disk quota exceeded)
+as the terminating condition. Only makes sense with sequential
write. For a read workload, the mount point will be filled first then I/O
-started on the result. This option doesn't make sense if operating on a raw
-device node, since the size of that is already known by the file system.
-Additionally, writing beyond end-of-device will not return ENOSPC there.
+started on the result.
.SS "I/O engine"
.TP
.BI ioengine \fR=\fPstr
sg engine includes engine specific options.
.TP
.B libzbc
-Synchronous I/O engine for SMR hard-disks using the \fBlibzbc\fR
-library. The target can be either an sg character device or
-a block device file. This engine supports the zonemode=zbd zone
-operations.
+Read, write, trim and ZBC/ZAC operations to a zoned block device using
+\fBlibzbc\fR library. The target can be either an SG character device or
+a block device file.
.TP
.B null
Doesn't transfer any data, just pretends to. This is mainly used to
and 'nrfiles', so that files will be created.
This engine is to measure file lookup and meta data access.
.TP
+.B filedelete
+Simply delete files by unlink() and do no I/O to the file. You need to set 'filesize'
+and 'nrfiles', so that files will be created.
+This engine is to measure file delete.
+.TP
.B libpmem
Read and write using mmap I/O to a file on a filesystem
mounted with DAX on a persistent memory device through the PMDK
I/O without transferring buffers between user-space and the kernel,
unless \fBverify\fR is set or \fBcuda_io\fR is \fBposix\fR. \fBiomem\fR must
not be \fBcudamalloc\fR. This ioengine defines engine specific options.
+.TP
+.B dfs
+I/O engine supporting asynchronous read and write operations to the DAOS File
+System (DFS) via libdfs.
+.TP
+.B nfs
+I/O engine supporting asynchronous read and write operations to
+NFS filesystems from userspace via libnfs. This is useful for
+achieving higher concurrency and thus throughput than is possible
+via kernel NFS.
+.TP
+.B exec
+Execute 3rd party tools. Could be used to perform monitoring during jobs runtime.
.SS "I/O engine specific parameters"
In addition, there are some parameters which are only valid when a specific
\fBioengine\fR is in use. These are used identically to normal parameters,
with the caveat that when used on the command line, they must come after the
\fBioengine\fR that defines them is selected.
.TP
-.BI (io_uring, libaio)cmdprio_percentage \fR=\fPint
-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 `direct=1' option must be used. fio must also be run as the root
-user.
+.BI (io_uring,libaio)cmdprio_percentage \fR=\fPint[,int]
+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 \fBlat_percentiles\fR is set, total latency (lat) will be reported.
+.TP
+.BI (io_uring,libaio)cmdprio_class \fR=\fPint[,int]
+Set the I/O priority class 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 the highest priority class. A single value applies
+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 \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.
+If not specified when \fBcmdprio_percentage\fR or \fBcmdprio_bssplit\fR
+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 man
+\fBionice\fR\|(1). Refer to an appropriate manpage for other operating systems
+since the meaning of priority may differ. See also the \fBprio\fR option.
+.TP
+.BI (io_uring,libaio)cmdprio_bssplit \fR=\fPstr[,str]
+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
+\fBbssplit\fR, that is, multiple different block sizes are used for reads and
+writes. The format for this option is the same as the format of the
+\fBbssplit\fR option, with the exception that values for trim IOs are
+ignored. This option is mutually exclusive with the \fBcmdprio_percentage\fR
+option.
.TP
.BI (io_uring)fixedbufs
If fio is asked to do direct IO, then Linux will map pages for each IO call, and
.BI (libhdfs)namenode \fR=\fPstr
The hostname or IP address of a HDFS cluster namenode to contact.
.TP
-.BI (libhdfs)port
+.BI (libhdfs)port \fR=\fPint
The listening port of the HFDS cluster namenode.
.TP
-.BI (netsplice,net)port
+.BI (netsplice,net)port \fR=\fPint
The TCP or UDP port to bind to or connect to. If this is used with
\fBnumjobs\fR to spawn multiple instances of the same job type, then
this will be the starting port number since fio will use a range of
ports.
.TP
-.BI (rdma)port
+.BI (rdma,librpma_*)port \fR=\fPint
The port to use for RDMA-CM communication. This should be the same
value on the client and the server side.
.TP
-.BI (netsplice,net, rdma)hostname \fR=\fPstr
+.BI (netsplice,net,rdma)hostname \fR=\fPstr
The hostname or IP address to use for TCP, UDP or RDMA-CM based I/O.
If the job is a TCP listener or UDP reader, the hostname is not used
and must be omitted unless it is a valid UDP multicast address.
.TP
+.BI (librpma_*)serverip \fR=\fPstr
+The IP address to be used for RDMA-CM based I/O.
+.TP
+.BI (librpma_*_server)direct_write_to_pmem \fR=\fPbool
+Set to 1 only when Direct Write to PMem from the remote host is possible. Otherwise, set to 0.
+.TP
+.BI (librpma_*_server)busy_wait_polling \fR=\fPbool
+Set to 0 to wait for completion instead of busy-wait polling completion.
+Default: 1.
+.TP
.BI (netsplice,net)interface \fR=\fPstr
The IP address of the network interface used to send or receive UDP
multicast.
Poll store instead of waiting for completion. Usually this provides better
throughput at cost of higher(up to 100%) CPU utilization.
.TP
+.BI (rados)touch_objects \fR=\fPbool
+During initialization, touch (create if do not exist) all objects (files).
+Touching all objects affects ceph caches and likely impacts test results.
+Enabled by default.
+.TP
.BI (http)http_host \fR=\fPstr
Hostname to connect to. For S3, this could be the bucket name. Default
is \fBlocalhost\fR
Specify stat system call type to measure lookup/getattr performance.
Default is \fBstat\fR for \fBstat\fR\|(2).
.TP
+.BI (sg)hipri
+If this option is set, fio will attempt to use polled IO completions. This
+will have a similar effect as (io_uring)hipri. Only SCSI READ and WRITE
+commands will have the SGV4_FLAG_HIPRI set (not UNMAP (trim) nor VERIFY).
+Older versions of the Linux sg driver that do not support hipri will simply
+ignore this flag and do normal IO. The Linux SCSI Low Level Driver (LLD)
+that "owns" the device also needs to support hipri (also known as iopoll
+and mq_poll). The MegaRAID driver is an example of a SCSI LLD.
+Default: clear (0) which does normal (interrupted based) IO.
+.TP
.BI (sg)readfua \fR=\fPbool
With readfua option set to 1, read operations include the force
unit access (fua) flag. Default: 0.
unit access (fua) flag. Default: 0.
.TP
.BI (sg)sg_write_mode \fR=\fPstr
-Specify the type of write commands to issue. This option can take three
+Specify the type of write commands to issue. This option can take multiple
values:
.RS
.RS
.B write (default)
Write opcodes are issued as usual
.TP
+.B write_and_verify
+Issue WRITE AND VERIFY commands. The BYTCHK bit is set to 00b. This directs the
+device to carry out a medium verification with no data comparison for the data
+that was written. The writefua option is ignored with this selection.
+.TP
.B 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.
+This option is deprecated. Use write_and_verify instead.
.TP
-.B same
+.B 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
generate 8k of data for each command butonly the first 512 bytes will
be used and transferred to the device. The writefua option is ignored
with this selection.
+.TP
+.B same
+This option is deprecated. Use write_same instead.
+.TP
+.B 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.
+.TP
+.B write_stream
+Issue WRITE STREAM(16) commands. Use the stream_id option to specify
+the stream identifier.
+.TP
+.B 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.
+.TP
+.B 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.
+.TP
+.B 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.
.RE
.RE
.TP
+.BI (sg)stream_id \fR=\fPint
+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.
+.TP
.BI (nbd)uri \fR=\fPstr
Specify the NBD URI of the server to test.
The string is a standard NBD URI (see
the use of cudaMemcpy.
.RE
.RE
+.TP
+.BI (dfs)pool
+Specify the label or UUID of the DAOS pool to connect to.
+.TP
+.BI (dfs)cont
+Specify the label or UUID of the DAOS container to open.
+.TP
+.BI (dfs)chunk_size
+Specificy a different chunk size (in bytes) for the dfs file.
+Use DAOS container's chunk size by default.
+.TP
+.BI (dfs)object_class
+Specificy a different object class for the dfs file.
+Use DAOS container's object class by default.
+.TP
+.BI (nfs)nfs_url
+URL in libnfs format, eg nfs://<server|ipv4|ipv6>/path[?arg=val[&arg=val]*]
+Refer to the libnfs README for more details.
+.TP
+.BI (exec)program\fR=\fPstr
+Specify the program to execute.
+Note the program will receive a SIGTERM when the job is reaching the time limit.
+A SIGKILL is sent once the job is over. The delay between the two signals is defined by \fBgrace_time\fR option.
+.TP
+.BI (exec)arguments\fR=\fPstr
+Specify arguments to pass to program.
+Some special variables can be expanded to pass fio's job details to the program :
+.RS
+.RS
+.TP
+.B %r
+replaced by the duration of the job in seconds
+.TP
+.BI %n
+replaced by the name of the job
+.RE
+.RE
+.TP
+.BI (exec)grace_time\fR=\fPint
+Defines the time between the SIGTERM and SIGKILL signals. Default is 1 second.
+.TP
+.BI (exec)std_redirect\fR=\fbool
+If set, stdout and stderr streams are redirected to files named from the job name. Default is true.
.SS "I/O depth"
.TP
.BI iodepth \fR=\fPint
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
-\fBthinktime_blocks\fR and \fBthinktime_spin\fR.
+\fBthinktime_blocks\fR, \fBthinktime_iotime\fR and \fBthinktime_spin\fR.
.TP
.BI thinktime_spin \fR=\fPtime
Only valid if \fBthinktime\fR is set - pretend to spend CPU time doing
queue depth setting redundant, since no more than 1 I/O will be queued
before we have to complete it and do our \fBthinktime\fR. In other words, this
setting effectively caps the queue depth if the latter is larger.
+.TP
+.BI thinktime_blocks_type \fR=\fPstr
+Only valid if \fBthinktime\fR is set - control how \fBthinktime_blocks\fR triggers.
+The default is `complete', which triggers \fBthinktime\fR when fio completes
+\fBthinktime_blocks\fR blocks. If this is set to `issue', then the trigger happens
+at the issue side.
+.TP
+.BI thinktime_iotime \fR=\fPtime
+Only valid if \fBthinktime\fR is set - control \fBthinktime\fR interval by time.
+The \fBthinktime\fR stall is repeated after IOs are executed for
+\fBthinktime_iotime\fR. 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, \fBthinktime_iotime\fR is interpreted as a number of seconds.
+If this option is used together with \fBthinktime_blocks\fR, the \fBthinktime\fR
+stall is repeated after \fBthinktime_iotime\fR or after \fBthinktime_blocks\fR
+IOs, whichever happens first.
+
.TP
.BI rate \fR=\fPint[,int][,int]
Cap the bandwidth used by this job. The number is in bytes/sec, the normal
queue depth that meets \fBlatency_target\fR and exit. If true, fio will continue
running and try to meet \fBlatency_target\fR by adjusting queue depth.
.TP
-.BI max_latency \fR=\fPtime
+.BI max_latency \fR=\fPtime[,time][,time]
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 interpreted in
-microseconds.
+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
between 0 and 7, with 0 being the highest. See man
\fBionice\fR\|(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 the I/O engine specific `cmdprio_percentage` and
+`cmdprio` options.
.TP
.BI prioclass \fR=\fPint
Set the I/O priority class. See man \fBionice\fR\|(1). For per-command
-priority setting, see I/O engine specific `cmdprio_percentage` and `hipri_percent`
-options.
+priority setting, see the I/O engine specific `cmdprio_percentage` and
+`cmdprio_class` options.
.TP
.BI cpus_allowed \fR=\fPstr
Controls the same options as \fBcpumask\fR, but accepts a textual
\fBwrite_bw_log\fR for details about the filename format and \fBLOG
FILE FORMATS\fR for how data is structured within the file.
.TP
+.BI log_entries \fR=\fPint
+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 allocation of new log entries,
+resulting in more precise time-related I/O statistics.
+Also see \fBlog_avg_msec\fR as well. Defaults to 1024.
+.TP
.BI log_avg_msec \fR=\fPint
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
entry as well as the other data values. Defaults to 0 meaning that
offsets are not present in logs. Also see \fBLOG FILE FORMATS\fR section.
.TP
+.BI log_prio \fR=\fPbool
+If this is set, the iolog options will include the I/O priority for the I/O
+entry as well as the other data values. Defaults to 0 meaning that
+I/O priorities are not present in logs. Also see \fBLOG FILE FORMATS\fR section.
+.TP
.BI log_compression \fR=\fPint
If this is set, fio will compress the I/O logs as it goes, to keep the
memory footprint lower. When a log reaches the specified size, that chunk is
from the start of the file for that particular I/O. The logging of the offset can be
toggled with \fBlog_offset\fR.
.P
-`Command priority` is 0 for normal priority and 1 for high priority. This is controlled
-by the ioengine specific \fBcmdprio_percentage\fR.
+If \fBlog_prio\fR is not set, the entry's `Command priority` is 1 for an IO executed
+with the highest RT priority class (\fBprioclass\fR=1 or \fBcmdprio_class\fR=1) and 0
+otherwise. This is controlled by the \fBprioclass\fR option and the ioengine specific
+\fBcmdprio_percentage\fR \fBcmdprio_class\fR options. If \fBlog_prio\fR is set, the
+entry's `Command priority` is the priority set for the IO, as a 16-bits hexadecimal
+number with the lowest 13 bits indicating the priority value (\fBprio\fR and
+\fBcmdprio\fR options) and the highest 3 bits indicating the IO priority class
+(\fBprioclass\fR and \fBcmdprio_class\fR options).
.P
Fio defaults to logging every individual I/O but when windowed logging is set
through \fBlog_avg_msec\fR, either the average (by default) or the maximum
projects / fio.git / blobdiff