Add 'per_job_logs' option

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index bcc72b5882be95e4804a641f151cde13b214b432..406cfca0d3ba855e5261878d66ae9fcd7c976723 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -435,6 +435,7 @@ unified_rw_reporting=bool   Fio normally reports statistics on a per
 
 randrepeat=bool        For random IO workloads, seed the generator in a predictable
                way so that results are repeatable across repetitions.
+               Defaults to true.
 
 randseed=int   Seed the random number generators based on this seed value, to
                be able to control what sequence of output is being generated.
@@ -1433,6 +1434,16 @@ replay_redirect=str While replaying I/O patterns using read_iolog the
                independent fio invocations.  Unfortuantely this also breaks
                the strict time ordering between multiple device accesses.
 
+replay_align=int       Force alignment of IO offsets and lengths in a trace
+               to this power of 2 value.
+
+replay_scale=int       Scale sector offsets down by this factor when
+               replaying traces.
+
+per_job_logs=bool      If set, this generates bw/clat/iops log with per
+               file private filenames. If not set, jobs with identical names
+               will share the log filename. Default: true.
+
 write_bw_log=str 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
@@ -1440,7 +1451,8 @@ write_bw_log=str If given, write a bandwidth log of the jobs in this job
                graphs. See write_lat_log for behaviour of given
                filename. For this option, the suffix is _bw.x.log, where
                x is the index of the job (1..N, where N is the number of
-               jobs).
+               jobs). If 'per_job_logs' is false, then the filename will not
+               include the job index.
 
 write_lat_log=str Same as write_bw_log, except that this option stores io
                submission, completion, and total latencies instead. If no
@@ -1453,13 +1465,17 @@ write_lat_log=str Same as write_bw_log, except that this option stores io
                The actual log names will be foo_slat.x.log, foo_clat.x.log,
                and foo_lat.x.log, where x is the index of the job (1..N,
                where N is the number of jobs). This helps fio_generate_plot
-               fine the logs automatically.
+               fine the logs automatically. If 'per_job_logs' is false, then
+               the filename will not include the job index.
+
 
 write_iops_log=str Same as write_bw_log, 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 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.
+               is given, fio will still append the type of log. If
+               'per_job_logs' is false, then the filename will not include
+               the job index.
 
 log_avg_msec=int By default, fio will log an entry in the iops, latency,
                or bw log for every IO that completes. When writing to the
@@ -2010,6 +2026,7 @@ before it can be used with this format. The offset and length are given in
 bytes. The action can be one of these:
 
 wait       Wait for 'offset' microseconds. Everything below 100 is discarded.
+          The time is relative to the previous wait statement.
 read       Read 'length' bytes beginning from 'offset'
 write      Write 'length' bytes beginning from 'offset'
 sync       fsync() the file