X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=fio.1;h=dc10b4031d9260817618033dc95218c73c96c446;hp=4fcd51182ad0c7e382f26bc4829bf0b56036e08b;hb=70e0c3166fdb8048b1e7f84be2371fc60af04f87;hpb=744492c94c22fbe805f6da31b19549374511f50e diff --git a/fio.1 b/fio.1 index 4fcd5118..dc10b403 100644 --- a/fio.1 +++ b/fio.1 @@ -53,6 +53,9 @@ Display usage information and exit. .TP .B \-\-version Display version information and exit. +.TP +.B \-\-terse\-version\fR=\fPtype +Terse version output format .SH "JOB FILE FORMAT" Job files are in `ini' format. They consist of one or more job definitions, which begin with a job name in square brackets and @@ -96,6 +99,10 @@ Integer range: a range of integers specified in the format \fIupper\fR may contain a suffix as described above. If an option allows two sets of ranges, they are separated with a `,' or `/' character. For example: `8\-8k/8M\-4G'. +.TP +.I float_list +List of floating numbers: A list of floating numbers, separated by +a ':' charcater. .SS "Parameter List" .TP .BI name \fR=\fPstr @@ -177,7 +184,10 @@ may still be skewed a bit, since the speed may be different. It is possible to specify a number of IO's to do before getting a new offset, this is one by appending a `:\fI\fR to the end of the string given. For a random read, it would look like \fBrw=randread:8\fR for passing in an offset modifier with a -value of 8. See the \fBrw_sequencer\fR option. +value of 8. If the postfix is used with a sequential IO pattern, then the value +specified will be added to the generated offset for each IO. For instance, +using \fBrw=write:4k\fR will skip 4k for every write. It turns sequential IO +into sequential IO with holes. See the \fBrw_sequencer\fR option. .RE .TP .BI rw_sequencer \fR=\fPstr @@ -319,6 +329,13 @@ default is to only fill it at init time and reuse that data. Only makes sense if zero_buffers isn't specified, naturally. If data verification is enabled, refill_buffers is also automatically enabled. .TP +.BI scramble_buffers \fR=\fPbool +If \fBrefill_buffers\fR is too costly and the target is using data +deduplication, then setting this option will slightly modify the IO buffer +contents to defeat normal de-dupe attempts. This is not enough to defeat +more clever block compression attempts, but it will stop naive dedupe +of blocks. Default: true. +.TP .BI nrfiles \fR=\fPint Number of files to use for this job. Default: 1. .TP @@ -360,7 +377,13 @@ Basic \fIreadv\fR\|(2) or \fIwritev\fR\|(2) I/O. Will emulate queuing by coalescing adjacents IOs into a single submission. .TP .B libaio -Linux native asynchronous I/O. +Linux native asynchronous I/O. This engine also has a sub-option, +\fBuserspace_reap\fR. To set it, use \fBioengine=libaio:userspace_reap\fR. +Normally, with the libaio engine in use, fio will use the +\fIio_getevents\fR\|(3) system call to reap newly returned events. With this +flag turned on, the AIO ring will be read directly from user-space to reap +events. The reaping mode is only enabled when polling for a minimum of \fB0\fR +events (eg when \fBiodepth_batch_complete=0\fR). .TP .B posixaio POSIX asynchronous I/O using \fIaio_read\fR\|(3) and \fIaio_write\fR\|(3). @@ -810,31 +833,31 @@ is to replay the IOPS onto the major/minor device that each IOP was recorded from. Setting \fBreplay_redirect\fR causes all IOPS to be replayed onto the single specified device regardless of the device it was recorded from. .TP -.B write_bw_log \fR=\fPstr +.BI write_bw_log \fR=\fPstr If given, write a bandwidth log of the jobs in this job file. Can be used to store data of the bandwidth of the jobs in their lifetime. The included fio_generate_plots script uses gnuplot to turn these text files into nice graphs. See \fBwrite_log_log\fR for behaviour of given filename. For this option, the postfix is _bw.log. .TP -.B write_lat_log \fR=\fPstr +.BI write_lat_log \fR=\fPstr Same as \fBwrite_bw_log\fR, but writes I/O completion latencies. If no filename is given with this option, the default filename of "jobname_type.log" is used. Even if the filename is given, fio will still append the type of log. .TP -.B disable_lat \fR=\fPbool +.BI disable_lat \fR=\fPbool Disable measurements of total latency numbers. Useful only for cutting back the number of calls to gettimeofday, as that does impact performance at really high IOPS rates. Note that to really get rid of a large amount of these calls, this option must be used with disable_slat and disable_bw as well. .TP -.B disable_clat \fR=\fPbool +.BI disable_clat \fR=\fPbool Disable measurements of completion latency numbers. See \fBdisable_lat\fR. .TP -.B disable_slat \fR=\fPbool +.BI disable_slat \fR=\fPbool Disable measurements of submission latency numbers. See \fBdisable_lat\fR. .TP -.B disable_bw_measurement \fR=\fPbool +.BI disable_bw_measurement \fR=\fPbool Disable measurements of throughput/bandwidth numbers. See \fBdisable_lat\fR. .TP .BI lockmem \fR=\fPint @@ -900,6 +923,17 @@ the thread/process does any work. .TP .BI gid \fR=\fPint Set group ID, see \fBuid\fR. +.TP +.BI clat_percentiles \fR=\fPbool +Enable the reporting of percentiles of completion latencies. +.TP +.BI percentile_list \fR=\fPfloat_list +Overwrite the default list of percentiles for completion +latencies. Each number is a floating number in the range (0,100], and +the maximum length of the list is 20. Use ':' to separate the +numbers. 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. .SH OUTPUT While running, \fBfio\fR will display the status of the created jobs. For example: @@ -1060,7 +1094,7 @@ change. The fields are: .P Read status: .RS -.B KB I/O, bandwidth \fR(KB/s)\fP, runtime \fR(ms)\fP +.B Total I/O \fR(KB)\fP, bandwidth \fR(KB/s)\fP, runtime \fR(ms)\fP .P Submission latency: .RS @@ -1082,7 +1116,7 @@ Bandwidth: .P Write status: .RS -.B KB I/O, bandwidth \fR(KB/s)\fP, runtime \fR(ms)\fP +.B Total I/O \fR(KB)\fP, bandwidth \fR(KB/s)\fP, runtime \fR(ms)\fP .P Submission latency: .RS