size, fio can alternate random and zeroed data throughout the IO buffer.
.TP
.BI buffer_pattern \fR=\fPstr
-If set, fio will fill the IO buffers with this pattern. If not set, the contents
-of IO buffers is defined by the other options related to buffer contents. The
-setting can be any pattern of bytes, and can be prefixed with 0x for hex
-values. It may also be a string, where the string must then be wrapped with
-"", e.g.:
+If set, fio will fill the I/O buffers with this pattern or with the contents
+of a file. If not set, the contents of I/O buffers are defined by the other
+options related to buffer contents. The setting can be any pattern of bytes,
+and can be prefixed with 0x for hex values. It may also be a string, where
+the string must then be wrapped with ``""``. Or it may also be a filename,
+where the filename must be wrapped with ``''`` in which case the file is
+opened and read. Note that not all the file contents will be read if that
+would cause the buffers to overflow. So, for example:
.RS
.RS
+\fBbuffer_pattern\fR='filename'
+.RS
+or
+.RE
\fBbuffer_pattern\fR="abcd"
.RS
or
Also you can combine everything together in any order:
.LP
.RS
-\fBbuffer_pattern\fR=0xdeadface"abcd"-12
+\fBbuffer_pattern\fR=0xdeadface"abcd"-12'filename'
.RE
.RE
.TP
Default: true.
.TP
.BI offset \fR=\fPint
-Offset in the file to start I/O. Data before the offset will not be touched.
+Start I/O at the provided offset in the file, given as either a fixed size or a
+percentage. If a percentage is given, the next \fBblockalign\fR-ed offset will
+be used. Data before the given offset will not be touched. This effectively
+caps the file size at (real_size - offset). Can be combined with \fBsize\fR to
+constrain the start and end range of the I/O workload.
.TP
.BI offset_increment \fR=\fPint
If this is provided, then the real offset becomes the
.P
.B text description (if provided in config - appears on newline)
.RE
+.P
+Below is a single line containing short names for each of the fields in
+the minimal output v3, separated by semicolons:
+.RS
+.P
+.nf
+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_max;read_clat_min;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_max;write_clat_min;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;pu_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
+.fi
+.RE
.SH TRACE FILE FORMAT
There are two trace file format that you can encounter. The older (v1) format
is unsupported since version 1.20-rc3 (March 2008). It will still be described
projects / fio.git / blobdiff