X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=HOWTO;h=8fad2ce6f4d889e8de2013391ee1dad00787681d;hp=4192ac73e1758d0daab27d68ba3443af7d1bdcf5;hb=13a85be93769986e03662e8dae6f8bfdf2971aa9;hpb=168bb5875da97004163c6b755de162ad481134c4 diff --git a/HOWTO b/HOWTO index 4192ac73..8fad2ce6 100644 --- a/HOWTO +++ b/HOWTO @@ -111,9 +111,6 @@ Command line options format. `json+` is like `json`, except it adds a full dump of the latency buckets. -.. option:: --runtime - Limit run time to runtime seconds. - .. option:: --bandwidth-log Generate aggregate bandwidth logs. @@ -185,8 +182,10 @@ Command line options .. option:: --status-interval=time - Force full status dump every `time` period passed. When the unit is - omitted, the value is interpreted in seconds. + Force a full status dump of cumulative (from job start) values at `time` + intervals. This option does *not* provide per-period measurements. So + values such as bandwidth are running averages. When the time unit is omitted, + `time` is interpreted in seconds. .. option:: --section=name @@ -950,7 +949,7 @@ I/O type .. option:: direct=bool If value is true, use non-buffered I/O. This is usually O_DIRECT. Note that - ZFS on Solaris doesn't support direct I/O. On Windows the synchronous + OpenBSD and ZFS on Solaris don't support direct I/O. On Windows the synchronous ioengines don't support direct I/O. Default: false. .. option:: atomic=bool @@ -1794,7 +1793,9 @@ I/O engine **external** Prefix to specify loading an external I/O engine object file. Append the engine filename, e.g. ``ioengine=external:/tmp/foo.o`` to load - ioengine :file:`foo.o` in :file:`/tmp`. + ioengine :file:`foo.o` in :file:`/tmp`. The path can be either + absolute or relative. See :file:`engines/skeleton_external.c` for + details of writing an external I/O engine. I/O engine specific parameters @@ -2861,7 +2862,15 @@ Measurements and reporting .. option:: clat_percentiles=bool - Enable the reporting of percentiles of completion latencies. + Enable the reporting of percentiles of completion latencies. This + option is mutually exclusive with :option:`lat_percentiles`. + +.. option:: lat_percentiles=bool + + Enable the reporting of percentiles of IO latencies. This is similar + to :option:`clat_percentiles`, except that this includes the + submission latency. This option is mutually exclusive with + :option:`clat_percentiles`. .. option:: percentile_list=float_list @@ -3382,6 +3391,15 @@ minimal output v3, separated by semicolons:: terse_version_3;fio_version;jobname;groupid;error;read_kb;read_bandwidth;read_iops;read_runtime_ms;read_slat_min;read_slat_max;read_slat_mean;read_slat_dev;read_clat_min;read_clat_max;read_clat_mean;read_clat_dev;read_clat_pct01;read_clat_pct02;read_clat_pct03;read_clat_pct04;read_clat_pct05;read_clat_pct06;read_clat_pct07;read_clat_pct08;read_clat_pct09;read_clat_pct10;read_clat_pct11;read_clat_pct12;read_clat_pct13;read_clat_pct14;read_clat_pct15;read_clat_pct16;read_clat_pct17;read_clat_pct18;read_clat_pct19;read_clat_pct20;read_tlat_min;read_lat_max;read_lat_mean;read_lat_dev;read_bw_min;read_bw_max;read_bw_agg_pct;read_bw_mean;read_bw_dev;write_kb;write_bandwidth;write_iops;write_runtime_ms;write_slat_min;write_slat_max;write_slat_mean;write_slat_dev;write_clat_min;write_clat_max;write_clat_mean;write_clat_dev;write_clat_pct01;write_clat_pct02;write_clat_pct03;write_clat_pct04;write_clat_pct05;write_clat_pct06;write_clat_pct07;write_clat_pct08;write_clat_pct09;write_clat_pct10;write_clat_pct11;write_clat_pct12;write_clat_pct13;write_clat_pct14;write_clat_pct15;write_clat_pct16;write_clat_pct17;write_clat_pct18;write_clat_pct19;write_clat_pct20;write_tlat_min;write_lat_max;write_lat_mean;write_lat_dev;write_bw_min;write_bw_max;write_bw_agg_pct;write_bw_mean;write_bw_dev;cpu_user;cpu_sys;cpu_csw;cpu_mjf;cpu_minf;iodepth_1;iodepth_2;iodepth_4;iodepth_8;iodepth_16;iodepth_32;iodepth_64;lat_2us;lat_4us;lat_10us;lat_20us;lat_50us;lat_100us;lat_250us;lat_500us;lat_750us;lat_1000us;lat_2ms;lat_4ms;lat_10ms;lat_20ms;lat_50ms;lat_100ms;lat_250ms;lat_500ms;lat_750ms;lat_1000ms;lat_2000ms;lat_over_2000ms;disk_name;disk_read_iops;disk_write_iops;disk_read_merges;disk_write_merges;disk_read_ticks;write_ticks;disk_queue_time;disk_util +JSON output +------------ + +The `json` output format is intended to be both human readable and convenient +for automated parsing. For the most part its sections mirror those of the +`normal` output. The `runtime` value is reported in msec and the `bw` value is +reported in 1024 bytes per second units. + + JSON+ output ------------