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
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
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. This option cannot be used
+with the `prio` or `prioclass` options. 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.
+.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, librpma_*)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.
.RE
.TP
.BI (dfs)pool
-Specify the UUID of the DAOS pool to connect to.
+Specify the label or UUID of the DAOS pool to connect to.
.TP
.BI (dfs)cont
-Specify the UUID of the DAOS DAOS container to open.
+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.
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
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
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
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