.SS "Time related parameters"
.TP
.BI runtime \fR=\fPtime
-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. When
-the unit is omitted, the value is interpreted in seconds.
+Limit runtime. The test will run until it completes the configured I/O
+workload or until it has run for this specified amount of time, whichever
+occurs first. 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. When the unit is omitted, the value is interpreted in
+seconds.
.TP
.BI time_based
If set, fio will run for the duration of the \fBruntime\fR specified
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
-should be reset periodically.
+A number between zero and one that indicates the ratio of written bytes in the
+zones with write pointers in the IO range to the size of the IO range. When
+current ratio is above this ratio, zones are reset periodically as
+\fBzone_reset_frequency\fR specifies. If there are multiple jobs when using this
+option, the IO range for all write jobs has to be the same.
.TP
.BI zone_reset_frequency \fR=\fPfloat
A number between zero and one that indicates how often a zone reset should be
OpenBSD and ZFS on Solaris don't support direct I/O. On Windows the synchronous
ioengines don't support direct I/O. Default: false.
.TP
-.BI atomic \fR=\fPbool
-If value is true, attempt to use atomic direct I/O. Atomic writes are
-guaranteed to be stable once acknowledged by the operating system. Only
-Linux supports O_ATOMIC right now.
-.TP
.BI buffered \fR=\fPbool
If value is true, use buffered I/O. This is the opposite of the
\fBdirect\fR option. Defaults to true.
.P
\fBsequential\fR is only useful for random I/O, where fio would normally
generate a new random offset for every I/O. If you append e.g. 8 to randread,
-you would get a new random offset for every 8 I/Os. The result would be a
-seek for only every 8 I/Os, instead of for every I/O. Use `rw=randread:8'
-to specify that. As sequential I/O is already sequential, setting
-\fBsequential\fR for that would not result in any differences. \fBidentical\fR
-behaves in a similar fashion, except it sends the same offset 8 number of
-times before generating a new offset.
+i.e. `rw=randread:8' you would get a new random offset for every 8 I/Os. The
+result would be a sequence of 8 sequential offsets with a random starting
+point. However this behavior may change if a sequential I/O reaches end of the
+file. As sequential I/O is already sequential, setting \fBsequential\fR for
+that would not result in any difference. \fBidentical\fR behaves in a similar
+fashion, except it sends the same offset 8 number of times before generating a
+new offset.
+.P
+.P
+Example #1:
+.RS
+.P
+.PD 0
+rw=randread:8
+.P
+rw_sequencer=sequential
+.P
+bs=4k
+.PD
+.RE
+.P
+The generated sequence of offsets will look like this:
+4k, 8k, 12k, 16k, 20k, 24k, 28k, 32k, 92k, 96k, 100k, 104k, 108k, 112k, 116k,
+120k, 48k, 52k ...
+.P
+.P
+Example #2:
+.RS
+.P
+.PD 0
+rw=randread:8
+.P
+rw_sequencer=identical
+.P
+bs=4k
+.PD
+.RE
+.P
+The generated sequence of offsets will look like this:
+4k, 4k, 4k, 4k, 4k, 4k, 4k, 4k, 92k, 92k, 92k, 92k, 92k, 92k, 92k, 92k, 48k,
+48k, 48k ...
.RE
.TP
.BI unified_rw_reporting \fR=\fPstr
.RE
.TP
.BI randrepeat \fR=\fPbool
-Seed the random number generator used for random I/O patterns in a
-predictable way so the pattern is repeatable across runs. Default: true.
+Seed all random number generators in a predictable way so the pattern is
+repeatable across runs. Default: true.
.TP
.BI allrandrepeat \fR=\fPbool
-Seed all random number generators in a predictable way so results are
-repeatable across runs. Default: false.
+Alias for \fBrandrepeat\fR. Default: true.
.TP
.BI randseed \fR=\fPint
Seed the random number generators based on this seed value, to be able to
.TP
.B random
Advise using FADV_RANDOM.
+.TP
+.B noreuse
+Advise using FADV_NOREUSE. This may be a no-op on older Linux
+kernels. Since Linux 6.3, it provides a hint to the LRU algorithm.
+See the \fBposix_fadvise\fR\|(2) man page.
.RE
.RE
.TP
before overwriting. The \fBtrimwrite\fR mode works well for this
constraint.
.TP
-.B pmemblk
-Read and write using filesystem DAX to a file on a filesystem
-mounted with DAX on a persistent memory device through the PMDK
-libpmemblk library.
-.TP
.B dev\-dax
Read and write using device DAX to a persistent memory device (e.g.,
/dev/dax0.0) through the PMDK libpmem library.
For direct I/O, requests will only succeed if cache invalidation isn't required,
file blocks are fully allocated and the disk request could be issued immediately.
.TP
+.BI (io_uring_cmd)fdp \fR=\fPbool
+Enable Flexible Data Placement mode for write commands.
+.TP
+.BI (io_uring_cmd)fdp_pli \fR=\fPstr
+Select which Placement ID Index/Indicies this job is allowed to use for writes.
+By default, the job will cycle through all available Placement IDs, so use this
+to isolate these identifiers to specific jobs. If you want fio to use placement
+identifier only at indices 0, 2 and 5 specify, you would set `fdp_pli=0,2,5`.
+.TP
.BI (cpuio)cpuload \fR=\fPint
Attempt to use the specified percentage of CPU cycles. This is a mandatory
option when using cpuio I/O engine.
.BI (xnvme)xnvme_dev_nsid\fR=\fPint
xnvme namespace identifier for userspace NVMe driver SPDK or vfio.
.TP
+.BI (xnvme)xnvme_dev_subnqn\fR=\fPstr
+Sets the subsystem NQN for fabrics. This is for xNVMe to utilize a fabrics
+target with multiple systems.
+.TP
+.BI (xnvme)xnvme_mem\fR=\fPstr
+Select the xnvme memory backend. This can take these values.
+.RS
+.RS
+.TP
+.B posix
+This is the default posix memory backend for linux NVMe driver.
+.TP
+.BI 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 XNVME_HUGETLB_PATH.
+.TP
+.BI spdk
+Uses SPDK's memory allocator.
+.TP
+.BI vfio
+Uses libvfn's memory allocator. This also specifies the use of libvfn backend
+instead of SPDK.
+.RE
+.RE
+.TP
.BI (xnvme)xnvme_iovec
If this option is set, xnvme will use vectored read/write commands.
.TP
.TP
.BI steadystate_duration \fR=\fPtime "\fR,\fP ss_dur" \fR=\fPtime
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. When the unit is omitted, the
-value is interpreted in seconds.
+has been reached. Data will be collected every \fBss_interval\fR. The default
+is 0 which disables steady state detection. When the unit is omitted, the value
+is interpreted in seconds.
.TP
.BI steadystate_ramp_time \fR=\fPtime "\fR,\fP ss_ramp" \fR=\fPtime
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. When the unit is omitted, the value is interpreted in seconds.
+.TP
+.BI steadystate_check_interval \fR=\fPtime "\fR,\fP ss_interval" \fR=\fPtime
+The values suring the rolling window will be collected with a period of this
+value. If \fBss_interval\fR is 30s and \fBss_dur\fR is 300s, 10 measurements
+will be taken. Default is 1s but that might not converge, especially for slower
+devices, so set this accordingly. When the unit is omitted, the value is
+interpreted in seconds.
.SS "Measurements and reporting"
.TP
.BI per_job_logs \fR=\fPbool
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