Merge branch 'openbsd_swap' of https://github.com/bsdkurt/fio

[fio.git] / fio.1

diff --git a/fio.1 b/fio.1
index a60863f62418e5bd778eff81eb366d21d82ecdb6..a58632b407fc2c95856278fc03a22aef34838f75 100644 (file)
--- a/fio.1
+++ b/fio.1
@@ -536,7 +536,7 @@ set fio will use the first listed directory, and thereby matching the
 specified, but lets all clones use the same file if set).
 .RS
 .P
-See the \fBfilename\fR option for information on how to escape ':' and '\\'
+See the \fBfilename\fR option for information on how to escape ':'
 characters within the directory path itself.
 .P
 Note: To control the directory fio will use for internal state files
@@ -557,10 +557,10 @@ by this option will be \fBsize\fR divided by number of files unless an
 explicit size is specified by \fBfilesize\fR.
 .RS
 .P
-Each colon and backslash in the wanted path must be escaped with a '\\'
+Each colon in the wanted path must be escaped with a '\\'
 character. For instance, if the path is `/dev/dsk/foo@3,0:c' then you
 would use `filename=/dev/dsk/foo@3,0\\:c' and if the path is
-`F:\\filename' then you would use `filename=F\\:\\\\filename'.
+`F:\\filename' then you would use `filename=F\\:\\filename'.
 .P
 On Windows, disk devices are accessed as `\\\\.\\PhysicalDrive0' for
 the first device, `\\\\.\\PhysicalDrive1' for the second etc.
@@ -1760,6 +1760,11 @@ Simply create the files and do no I/O to them.  You still need to set
 \fBfilesize\fR so that all the accounting still occurs, but no actual I/O will be
 done other than creating the file.
 .TP
+.B filestat
+Simply do stat() 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 lookup and meta data access.
+.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
@@ -1790,12 +1795,12 @@ In addition, there are some parameters which are only valid when a specific
 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)hipri
-If this option is set, fio will attempt to use polled IO completions. Normal IO
-completions generate interrupts to signal the completion of IO, polled
-completions do not. Hence they are require active reaping by the application.
-The benefits are more efficient IO for high IOPS scenarios, and lower latencies
-for low queue depth IO.
+.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.
 .TP
 .BI (io_uring)fixedbufs
 If fio is asked to do direct IO, then Linux will map pages for each IO call, and
@@ -1803,6 +1808,13 @@ release them when IO is done. If this option is set, the pages are pre-mapped
 before IO is started. This eliminates the need to map and release for each IO.
 This is more efficient, and reduces the IO latency as well.
 .TP
+.BI (io_uring)hipri
+If this option is set, fio will attempt to use polled IO completions. Normal IO
+completions generate interrupts to signal the completion of IO, polled
+completions do not. Hence they are require active reaping by the application.
+The benefits are more efficient IO for high IOPS scenarios, and lower latencies
+for low queue depth IO.
+.TP
 .BI (io_uring)registerfiles
 With this option, fio registers the set of files being used with the kernel.
 This avoids the overhead of managing file counts in the kernel, making the
@@ -2020,6 +2032,9 @@ on the client site it will be used in the rdma_resolve_add()
 function. This can be useful when multiple paths exist between the
 client and the server or in certain loopback configurations.
 .TP
+.BI (filestat)lstat \fR=\fPbool
+Use \fBlstat\fR\|(2) to measure lookup/getattr performance. Default: 0.
+.TP
 .BI (sg)readfua \fR=\fPbool
 With readfua option set to 1, read operations include the force
 unit access (fua) flag. Default: 0.
@@ -2277,7 +2292,7 @@ to replay a workload captured by blktrace. See
 replay, the file needs to be turned into a blkparse binary data file first
 (`blkparse <device> \-o /dev/null \-d file_for_fio.bin').
 You can specify a number of files by separating the names with a ':' character.
-See the \fBfilename\fR option for information on how to escape ':' and '\'
+See the \fBfilename\fR option for information on how to escape ':'
 characters within the file names. These files will be sequentially assigned to
 job clones created by \fBnumjobs\fR.
 .TP
@@ -2381,10 +2396,14 @@ priority class.
 Set the I/O priority value of this job. Linux limits us to a positive value
 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.
+systems since meaning of priority may differ. For per-command priority
+setting, see I/O engine specific `cmdprio_percentage` and `hipri_percentage`
+options.
 .TP
 .BI prioclass \fR=\fPint
-Set the I/O priority class. See man \fBionice\fR\|(1).
+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.
 .TP
 .BI cpus_allowed \fR=\fPstr
 Controls the same options as \fBcpumask\fR, but accepts a textual