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.
.. 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
.. option:: --max-jobs=nr
Set the maximum number of threads/processes to support to `nr`.
+ NOTE: On Linux, it may be necessary to increase the shared-memory
+ limit ('/proc/sys/kernel/shmmax') if fio runs into errors while
+ creating jobs.
.. option:: --server=args
prefixes. To specify power-of-10 decimal values defined in the
International System of Units (SI):
- * *Ki* -- means kilo (K) or 1000
- * *Mi* -- means mega (M) or 1000**2
- * *Gi* -- means giga (G) or 1000**3
- * *Ti* -- means tera (T) or 1000**4
- * *Pi* -- means peta (P) or 1000**5
+ * *K* -- means kilo (K) or 1000
+ * *M* -- means mega (M) or 1000**2
+ * *G* -- means giga (G) or 1000**3
+ * *T* -- means tera (T) or 1000**4
+ * *P* -- means peta (P) or 1000**5
To specify power-of-2 binary values defined in IEC 80000-13:
- * *K* -- means kibi (Ki) or 1024
- * *M* -- means mebi (Mi) or 1024**2
- * *G* -- means gibi (Gi) or 1024**3
- * *T* -- means tebi (Ti) or 1024**4
- * *P* -- means pebi (Pi) or 1024**5
+ * *Ki* -- means kibi (Ki) or 1024
+ * *Mi* -- means mebi (Mi) or 1024**2
+ * *Gi* -- means gibi (Gi) or 1024**3
+ * *Ti* -- means tebi (Ti) or 1024**4
+ * *Pi* -- means pebi (Pi) or 1024**5
With :option:`kb_base`\=1024 (the default), the unit prefixes are opposite
from those specified in the SI and IEC 80000-13 standards to provide
.. 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
**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.
+ **filecreate**
+ Simply create the files and do no IO to them. You still need to
+ set `filesize` so that all the accounting still occurs, but no
+ actual IO will be done other than creating the file.
I/O engine specific parameters
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.. 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
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
------------
on the type of log, it will be one of the following:
**Latency log**
- Value is latency in usecs
+ Value is latency in nsecs
**Bandwidth log**
Value is in KiB/sec
**IOPS log**