cmdprio_bssplit=blocksize/percentage/class/level/hint:...
.RE
.P
-This is an extension of the second accepted format that allows to also
+This is an extension of the second accepted format that allows one to also
specify a priority hint.
.P
For all formats, only the read and write data directions are supported, values
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)
.TP
.BI (io_uring_cmd)pi_chk \fR=\fPstr[,str][,str]
Controls the protection information check. This can take one or more of these
.TP
.B unix
UNIX domain socket.
+.TP
+.B vsock
+VSOCK protocol.
.RE
.P
-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 \fBfilename\fR option should be used and the port is invalid.
+When the protocol is VSOCK, the \fBhostname\fR is the CID of the remote VM.
+
.RE
.TP
.BI (netsplice,net)listen
.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.
+set an environment variable for XNVME_HUGETLB_PATH.
.TP
.BI spdk
Uses SPDK's memory allocator.
A colon-separated list of additional libblkio properties to be set after
creating but before connecting the libblkio instance. Each property must have
the format \fB<name>=<value>\fR. Colons can be escaped as \fB\\:\fR. These are
-set after the engine sets any other properties, so those can be overriden.
+set after the engine sets any other properties, so those can be overridden.
Available properties depend on the libblkio version in use and are listed at
\fIhttps://libblkio.gitlab.io/libblkio/blkio.html#properties\fR
.TP
A colon-separated list of additional libblkio properties to be set after
connecting but before starting the libblkio instance. Each property must have
the format \fB<name>=<value>\fR. Colons can be escaped as \fB\\:\fR. These are
-set after the engine sets any other properties, so those can be overriden.
+set after the engine sets any other properties, so those can be overridden.
Available properties depend on the libblkio version in use and are listed at
\fIhttps://libblkio.gitlab.io/libblkio/blkio.html#properties\fR
.TP
problem). Note that this option cannot reliably be used with async IO engines.
.SS "I/O rate"
.TP
+.BI thinkcycles \fR=\fPint
+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 \fBthinktime\fR.
+Might not have any effect on some platforms, this can be checked by trying a setting
+a high enough amount of thinkcycles.
+.TP
.BI thinktime \fR=\fPtime
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.
.SS "Measurements and reporting"
.TP
.BI per_job_logs \fR=\fPbool
-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:
+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.
.TP
.BI group_reporting
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
-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
-\fBlog_max_value\fR as well. Defaults to 0, logging all entries.
-Also see \fBLOG FILE FORMATS\fR section.
+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 \fBlog_window_value\fR as well. Defaults
+to 0, logging entries for each I/O. Also see \fBLOG FILE FORMATS\fR section.
.TP
.BI log_hist_msec \fR=\fPint
Same as \fBlog_avg_msec\fR, but logs entries for completion latency
in coarseness, fio outputs half as many bins. Defaults to 0, for which
histogram logs contain 1216 latency bins. See \fBLOG FILE FORMATS\fR section.
.TP
-.BI log_max_value \fR=\fPbool
-If \fBlog_avg_msec\fR 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.
+.BI log_window_value \fR=\fPstr "\fR,\fP log_max_value" \fR=\fPstr
+If \fBlog_avg_msec\fR 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:
+.RS
+.TP
+.B avg
+Log average value over the window. The default.
+.TP
+.B max
+Log maximum value in the window.
+.TP
+.B both
+Log both average and maximum value over the window.
+.TP
+.B 0
+Backward-compatible alias for \fBavg\fR.
+.TP
+.B 1
+Backward-compatible alias for \fBmax\fR.
+.RE
.TP
.BI log_offset \fR=\fPbool
If this is set, the iolog options will include the byte offset for the I/O
(\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
-(\fBlog_max_value\fR 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 \fBlog_avg_msec\fR, either the average (by default), the maximum
+(\fBlog_window_value\fR is set to max) `value' seen over the specified period of
+time, or both the average `value' and maximum `value1' (\fBlog_window_value\fR is
+set to both) is recorded. The log file format when both the values are reported
+takes this form:
+.RS
+.P
+time (msec), value, value1, data direction, block size (bytes), offset (bytes),
+command priority
+.RE
+.P
+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.
.SH CLIENT / SERVER
Normally fio is invoked as a stand-alone application on the machine where the
I/O workload should be generated. However, the backend and frontend of fio can
projects / fio.git / blobdiff