Add 'allow_mounted_write' option

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index 0808cc3a07e0f53a62c3476b6789f47426917829..ab0250cb60e6d84cde61f67916f8b48cef6ee843 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.
@@ -1198,6 +1199,17 @@ create_only=bool If true, fio will only run the setup phase of the job.
                        that will be done. The actual job contents are not
                        executed.
 
+allow_file_create=bool If true, fio is permitted to create files as part
+               of its workload. This is the default behavior. If this
+               option is false, then fio will error out if the files it
+               needs to use don't already exist. Default: true.
+
+allow_mounted_write=bool       If this isn't set, fio will abort jobs that
+               are destructive (eg that write) to what appears to be a
+               mounted device or partition. This should help catch creating
+               inadvertently destructive tests, not realizing that the test
+               will destroy data on the mounted file system. Default: false.
+
 pre_read=bool  If this is given, files will be pre-read into memory before
                starting the given IO operation. This will also clear
                the 'invalidate' flag, since it is pointless to pre-read
@@ -1439,6 +1451,10 @@ replay_align=int Force alignment of IO offsets and lengths in a trace
 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
@@ -1446,7 +1462,8 @@ 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
@@ -1459,13 +1476,17 @@ 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