X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=fio.1;h=f134e0bf88ca9f958f1e8bdec594f3551e1ceb9d;hb=8644ef7c4c49aa6d6492b3b250a06b841496d7fd;hp=6283fc1d92931fd860915c92735d0f9136c3ac7e;hpb=73ccd14e52d1379fb0848811894125a5a8cd954a;p=fio.git diff --git a/fio.1 b/fio.1 index 6283fc1d..f134e0bf 100644 --- a/fio.1 +++ b/fio.1 @@ -804,7 +804,11 @@ so. Default: false. When running a random write test across an entire drive many more zones will be open than in a typical application workload. Hence this command line option that allows to limit the number of open zones. The number of open zones is -defined as the number of zones to which write commands are issued. +defined as the number of zones to which write commands are issued by all +threads/processes. +.TP +.BI job_max_open_zones \fR=\fPint +Limit on the number of simultaneously opened zones per single thread/process. .TP .BI zone_reset_threshold \fR=\fPfloat A number between zero and one that indicates the ratio of logical blocks with @@ -1629,6 +1633,12 @@ I/O. Requires \fBfilename\fR option to specify either block or character devices. This engine supports trim operations. The 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. +.TP .B null Doesn't transfer any data, just pretends to. This is mainly used to exercise fio itself and for debugging/testing purposes. @@ -1795,12 +1805,13 @@ 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. fio must also be run as the root +user. .TP .BI (io_uring)fixedbufs If fio is asked to do direct IO, then Linux will map pages for each IO call, and @@ -1808,6 +1819,13 @@ 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 @@ -1839,6 +1857,22 @@ than normal. When hipri is set this determines the probability of a pvsync2 I/O being high priority. The default is 100%. .TP +.BI (pvsync2,libaio,io_uring)nowait +By default if a request cannot be executed immediately (e.g. resource starvation, +waiting on locks) it is queued and the initiating process will be blocked until +the required resource becomes free. +This option sets the RWF_NOWAIT flag (supported from the 4.14 Linux kernel) and +the call will return instantly with EAGAIN or a partial result rather than waiting. + +It is useful to also use \fBignore_error\fR=EAGAIN when using this option. +Note: glibc 2.27, 2.28 have a bug in syscall wrappers preadv2, pwritev2. +They return EOPNOTSUP instead of EAGAIN. + +For cached I/O, using this option usually means a request operates only with +cached data. Currently the RWF_NOWAIT flag does not supported for cached write. +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 (cpuio)cpuload \fR=\fPint Attempt to use the specified percentage of CPU cycles. This is a mandatory option when using cpuio I/O engine. @@ -2025,6 +2059,10 @@ 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)stat_type \fR=\fPstr +Specify stat system call type to measure lookup/getattr performance. +Default is \fBstat\fR for \fBstat\fR\|(2). +.TP .BI (sg)readfua \fR=\fPbool With readfua option set to 1, read operations include the force unit access (fua) flag. Default: 0. @@ -2258,6 +2296,11 @@ The percentage of I/Os that must fall within the criteria specified by defaults to 100.0, meaning that all I/Os must be equal or below to the value set by \fBlatency_target\fR. .TP +.BI latency_run \fR=\fPbool +Used with \fBlatency_target\fR. If false (default), fio will find the highest +queue depth that meets \fBlatency_target\fR and exit. If true, fio will continue +running and try to meet \fBlatency_target\fR by adjusting queue depth. +.TP .BI max_latency \fR=\fPtime If set, fio will exit the job with an ETIMEDOUT error if it exceeds this maximum latency. When the unit is omitted, the value is interpreted in @@ -2386,10 +2429,14 @@ 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 @@ -2986,23 +3033,24 @@ Disable measurements of submission latency numbers. See Disable measurements of throughput/bandwidth numbers. See \fBdisable_lat\fR. .TP +.BI slat_percentiles \fR=\fPbool +Report submission latency percentiles. Submission latency is not recorded +for synchronous ioengines. +.TP .BI clat_percentiles \fR=\fPbool -Enable the reporting of percentiles of completion latencies. This option is -mutually exclusive with \fBlat_percentiles\fR. +Report completion latency percentiles. .TP .BI lat_percentiles \fR=\fPbool -Enable the reporting of percentiles of I/O latencies. This is similar to -\fBclat_percentiles\fR, except that this includes the submission latency. -This option is mutually exclusive with \fBclat_percentiles\fR. +Report total latency percentiles. Total latency is the sum of submission +latency and completion latency. .TP .BI percentile_list \fR=\fPfloat_list -Overwrite the default list of percentiles for completion latencies and the -block error histogram. Each number is a floating number in the range +Overwrite the default list of percentiles for latencies and the +block error histogram. Each number is a floating point number in the range (0,100], and the maximum length of the list is 20. Use ':' to separate the -numbers, and list the numbers in ascending order. For example, -`\-\-percentile_list=99.5:99.9' will cause fio to report the values of -completion latency below which 99.5% and 99.9% of the observed latencies -fell, respectively. +numbers. For example, `\-\-percentile_list=99.5:99.9' will cause fio to +report the latency durations below which 99.5% and 99.9% of the observed +latencies fell, respectively. .TP .BI significant_figures \fR=\fPint If using \fB\-\-output\-format\fR of `normal', set the significant figures @@ -3815,7 +3863,8 @@ Fio supports a variety of log file formats, for logging latencies, bandwidth, and IOPS. The logs share a common format, which looks like this: .RS .P -time (msec), value, data direction, block size (bytes), offset (bytes) +time (msec), value, data direction, block size (bytes), offset (bytes), +command priority .RE .P `Time' for the log entry is always in milliseconds. The `value' logged depends @@ -3849,6 +3898,9 @@ The entry's `block size' is always in bytes. The `offset' is the position in byt 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. +.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