X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=fio.1;h=a58632b407fc2c95856278fc03a22aef34838f75;hb=56440e63ac17d020a58e20a2341333a98f18a7ff;hp=aaa3e99f2b74f7c85cff4f6685c12c802cbc8925;hpb=338f2db5ba045ee4be7ce441dd4ded62de849b65;p=fio.git diff --git a/fio.1 b/fio.1 index aaa3e99f..a58632b4 100644 --- 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. @@ -943,6 +943,10 @@ Pre-allocate via \fBposix_fallocate\fR\|(3). Pre-allocate via \fBfallocate\fR\|(2) with FALLOC_FL_KEEP_SIZE set. .TP +.B truncate +Extend file to final size using \fBftruncate\fR|(2) +instead of allocating. +.TP .B 0 Backward-compatible alias for \fBnone\fR. .TP @@ -953,7 +957,15 @@ Backward-compatible alias for \fBposix\fR. May not be available on all supported platforms. \fBkeep\fR is only available on Linux. If using ZFS on Solaris this cannot be set to \fBposix\fR because ZFS doesn't support pre-allocation. Default: \fBnative\fR if any -pre-allocation methods are available, \fBnone\fR if not. +pre-allocation methods except \fBtruncate\fR are available, \fBnone\fR if not. +.P +Note that using \fBtruncate\fR on Windows will interact surprisingly +with non-sequential write patterns. When writing to a file that has +been extended by setting the end-of-file information, Windows will +backfill the unwritten portion of the file up to that offset with +zeroes before issuing the new write. This means that a single small +write to the end of an extended file will stall until the entire +file has been filled with zeroes. .RE .TP .BI fadvise_hint \fR=\fPstr @@ -1748,6 +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 @@ -1778,12 +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 @@ -1791,6 +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 @@ -2008,6 +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. @@ -2265,7 +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 \-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 @@ -2369,10 +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 @@ -2411,7 +2442,7 @@ Each job will get a unique CPU from the CPU set. .RE .P \fBshared\fR is the default behavior, if the option isn't specified. If -\fBsplit\fR is specified, then fio will will assign one cpu per job. If not +\fBsplit\fR is specified, then fio will assign one cpu per job. If not enough CPUs are given for the jobs listed, then fio will roundrobin the CPUs in the set. .RE @@ -2497,9 +2528,20 @@ wall also implies starting a new reporting group, see \fBgroup_reporting\fR. .TP .BI exitall -By default, fio will continue running all other jobs when one job finishes -but sometimes this is not the desired action. Setting \fBexitall\fR will -instead make fio terminate all other jobs when one job finishes. +By default, fio will continue running all other jobs when one job finishes. +Sometimes this is not the desired action. Setting \fBexitall\fR will instead +make fio terminate all jobs in the same group, as soon as one job of that +group finishes. +.TP +.BI exit_what +By default, fio will continue running all other jobs when one job finishes. +Sometimes this is not the desired action. Setting \fBexit_all\fR will instead +make fio terminate all jobs in the same group. The option \fBexit_what\fR +allows to control which jobs get terminated when \fBexitall\fR is enabled. The +default is \fBgroup\fR and does not change the behaviour of \fBexitall\fR. The +setting \fBall\fR terminates all jobs. The setting \fBstonewall\fR terminates +all currently running jobs across all groups and continues execution with the +next stonewalled group. .TP .BI exec_prerun \fR=\fPstr Before running this job, issue the command specified through