Limit run time to \fIruntime\fR seconds.
.TP
.B \-\-bandwidth\-log
-Generate per-job bandwidth logs.
+Generate aggregate bandwidth logs.
.TP
.B \-\-minimal
Print statistics in a terse, semicolon-delimited format.
\fBiodepth_batch_complete_max\fR=<iodepth>
.RE
-which means that we will retrieve at leat 1 IO and up to the
+which means that we will retrieve at least 1 IO and up to the
whole submitted queue depth. If none of IO has been completed
yet, we will wait.
.BI unlink \fR=\fPbool
Unlink job files when done. Default: false.
.TP
+.BI unlink_each_loop \fR=\fPbool
+Unlink job files after each iteration or loop. Default: false.
+.TP
.BI loops \fR=\fPint
Specifies the number of iterations (runs of the same workload) of this job.
Default: 1.
decimal or a hex number). The verify_pattern if larger than a 32-bit quantity
has to be a hex number that starts with either "0x" or "0X". Use with
\fBverify\fP=str. Also, verify_pattern supports %o format, which means that for
-each block offset will be written and then verifyied back, e.g.:
+each block offset will be written and then verified back, e.g.:
.RS
.RS
\fBverify_pattern\fR=%o
not set, jobs with identical names will share the log filename. Default: true.
.TP
.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_lat_log\fR for behaviour of given filename. For this
-option, the postfix is _bw.x.log, where x is the index of the job (1..N,
-where N is the number of jobs). If \fBper_job_logs\fR is false, then the
-filename will not include the job index. See the \fBLOG FILE FORMATS\fR
+If given, write a bandwidth log for this job. 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_lat_log\fR
+for behaviour of given filename. For this option, the postfix is _bw.x.log,
+where x is the index of the job (1..N, where N is the number of jobs). If
+\fBper_job_logs\fR is false, then the filename will not include the job index.
+See the \fBLOG FILE FORMATS\fR
section.
.TP
.BI write_lat_log \fR=\fPstr
append the type of log. If \fBper_job_logs\fR is false, then the filename will
not include the job index. See the \fBLOG FILE FORMATS\fR section.
.TP
+.BI write_hist_log \fR=\fPstr
+Same as \fBwrite_lat_log\fR, but writes I/O completion latency histograms. If
+no filename is given with this option, the default filename of
+"jobname_clat_hist.x.log" is used, where x is the index of the job (1..N, where
+N is the number of jobs). Even if the filename is given, fio will still append
+the type of log. If \fBper_job_logs\fR is false, then the filename will not
+include the job index. See the \fBLOG FILE FORMATS\fR section.
+.TP
.BI write_iops_log \fR=\fPstr
Same as \fBwrite_bw_log\fR, but writes IOPS. If no filename is given with this
option, the default filename of "jobname_type.x.log" is used, where x is the
instead want to log the maximum value, set this option to 1. Defaults to
0, meaning that averaged values are logged.
.TP
+.BI log_hist_msec \fR=\fPint
+Same as \fBlog_avg_msec\fR, but logs entries for completion latency histograms.
+Computing latency percentiles from averages of intervals using \fBlog_avg_msec\fR
+is innacurate. Setting this option makes fio log histogram entries over the
+specified period of time, reducing log sizes for high IOPS devices while
+retaining percentile accuracy. See \fBlog_hist_coarseness\fR as well. Defaults
+to 0, meaning histogram logging is disabled.
+.TP
+.BI log_hist_coarseness \fR=\fPint
+Integer ranging from 0 to 6, defining the coarseness of the resolution of the
+histogram logs enabled with \fBlog_hist_msec\fR. For each increment in
+coarseness, fio outputs half as many bins. Defaults to 0, for which histogram
+logs contain 1216 latency bins. See the \fBLOG FILE FORMATS\fR section.
+.TP
.BI log_offset \fR=\fPbool
If this is set, the iolog options will include the byte offset for the IO
entry as well as the other data values.
decompressed with fio, using the \fB\-\-inflate-log\fR command line parameter.
The files will be stored with a \fB\.fz\fR suffix.
.TP
+.BI log_unix_epoch \fR=\fPbool
+If set, fio will log Unix timestamps to the log files produced by enabling
+\fBwrite_type_log\fR for each log type, instead of the default zero-based
+timestamps.
+.TP
.BI block_error_percentiles \fR=\fPbool
If set, record errors in trim block-sized units from writes and trims and output
a histogram of how many trims it took to get to errors, and what kind of error
used identically to normal parameters, with the caveat that when used on the
command line, they must come after the ioengine.
.TP
-.BI (cpu)cpuload \fR=\fPint
+.BI (cpuio)cpuload \fR=\fPint
Attempt to use the specified percentage of CPU cycles.
.TP
-.BI (cpu)cpuchunks \fR=\fPint
+.BI (cpuio)cpuchunks \fR=\fPint
Split the load into cycles of the given time. In microseconds.
.TP
-.BI (cpu)exit_on_io_done \fR=\fPbool
+.BI (cpuio)exit_on_io_done \fR=\fPbool
Detect when IO threads are done, then exit.
.TP
.BI (libaio)userspace_reap
The \fIoffset\fR is the offset, in bytes, from the start of the file, for that
particular IO. The logging of the offset can be toggled with \fBlog_offset\fR.
-If windowed logging is enabled though \fBlog_avg_msec\fR, then fio doesn't log
+If windowed logging is enabled through \fBlog_avg_msec\fR, then fio doesn't log
individual IOs. Instead of logs the average values over the specified
period of time. Since \fIdata direction\fR and \fIoffset\fR are per-IO values,
they aren't applicable if windowed logging is enabled. If windowed logging
is enabled and \fBlog_max_value\fR is set, then fio logs maximum values in
that window instead of averages.
+For histogram logging the logs look like this:
+
+.B time (msec), data direction, block-size, bin 0, bin 1, ..., bin 1215
+
+Where 'bin i' gives the frequency of IO requests with a latency falling in
+the i-th bin. See \fBlog_hist_coarseness\fR for logging fewer bins.
+
.RE
.SH CLIENT / SERVER
projects / fio.git / blobdiff