and it will start doing what the job_file tells it to do. You can give
more than one job file on the command line, fio will serialize the running
of those files. Internally that is the same as using the 'stonewall'
-parameter described the the parameter section.
+parameter described in the parameter section.
If the job file contains only one job, you may as well just give the
parameters on the command line. The command line parameters are identical
Unless specific nrfiles and filesize options are given,
fio will divide this size between the available files
specified by the job. If not set, fio will use the full
- size of the given files or devices. If the the files
- do not exist, size must be given. It is also possible to
- give size as a percentage between 1 and 100. If size=20%
- is given, fio will use 20% of the full size of the given
+ size of the given files or devices. If the files do not
+ exist, size must be given. It is also possible to give
+ size as a percentage between 1 and 100. If size=20% is
+ given, fio will use 20% of the full size of the given
files or devices.
io_limit=int Normally fio operates within the region set by 'size', which
jobs in their lifetime. The included fio_generate_plots
script uses gnuplot to turn these text files into nice
graphs. See write_lat_log for behaviour of given
- filename. For this option, the suffix is _bw.log.
+ 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).
write_lat_log=str Same as write_bw_log, except that this option stores io
submission, completion, and total latencies instead. If no
write_lat_log=foo
- The actual log names will be foo_slat.log, foo_clat.log,
- and foo_lat.log. This helps fio_generate_plot fine the logs
- automatically.
+ 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.
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.log" is used. Even if the filename is given,
- fio will still append the type of log.
+ "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.
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
specified period of time, reducing the resolution of the log.
Defaults to 0.
+log_offset=int If this is set, the iolog options will include the byte
+ offset for the IO entry as well as the other data values.
+
+log_compression=int If this is set, fio will compress the IO logs as
+ it goes, to keep the memory footprint lower. When a log
+ reaches the specified size, that chunk is removed and
+ compressed in the background. Given that IO logs are
+ fairly highly compressible, this yields a nice memory
+ savings for longer runs. The downside is that the
+ compression will consume some background CPU cycles, so
+ it may impact the run. This, however, is also true if
+ the logging ends up consuming most of the system memory.
+ So pick your poison. The IO logs are saved normally at the
+ end of a run, by decompressing the chunks and storing them
+ in the specified log file. This feature depends on the
+ availability of zlib.
+
+log_store_compressed=bool If set, and log_compression is also set,
+ fio will store the log files in a compressed format. They
+ can be decompressed with fio, using the --inflate-log
+ command line parameter. The files will be stored with a
+ .fz suffix.
+
lockmem=int Pin down the specified amount of memory with mlock(2). Can
potentially be used instead of removing memory or booting
with less memory to simulate a smaller amount of memory.