.. option:: --debug=type
- Enable verbose tracing of various fio actions. May be ``all`` for all types
+ Enable verbose tracing `type` of various fio actions. May be ``all`` for all types
or individual types separated by a comma (e.g. ``--debug=file,mem`` will
enable file and memory debugging). Currently, additional logging is
available for:
Write output to file `filename`.
-.. option:: --output-format=type
+.. option:: --output-format=format
- Set the reporting format to `normal`, `terse`, `json`, or `json+`. Multiple
+ Set the reporting `format` to `normal`, `terse`, `json`, or `json+`. Multiple
formats can be selected, separated by a comma. `terse` is a CSV based
format. `json+` is like `json`, except it adds a full dump of the latency
buckets.
-.. option:: --runtime
- Limit run time to runtime seconds.
-
.. option:: --bandwidth-log
Generate aggregate bandwidth logs.
**Deprecated**, use :option:`--output-format` instead to select multiple
formats.
-.. option:: --terse-version=type
+.. option:: --terse-version=version
- Set terse version output format (default 3, or 2 or 4 or 5).
+ Set terse `version` output format (default 3, or 2 or 4 or 5).
.. option:: --version
.. option:: --enghelp=[ioengine[,command]]
- List all commands defined by :option:`ioengine`, or print help for `command`
- defined by :option:`ioengine`. If no :option:`ioengine` is given, list all
+ List all commands defined by `ioengine`, or print help for `command`
+ defined by `ioengine`. If no `ioengine` is given, list all
available ioengines.
.. option:: --showcmd=jobfile
.. option:: --status-interval=time
- Force full status dump every `time` period passed. When the unit is
- omitted, the value is interpreted in seconds.
+ Force a full status dump of cumulative (from job start) values at `time`
+ intervals. This option does *not* provide per-period measurements. So
+ values such as bandwidth are running averages. When the time unit is omitted,
+ `time` is interpreted in seconds.
.. option:: --section=name
.. option:: --max-jobs=nr
- Set the maximum number of threads/processes to support.
+ Set the maximum number of threads/processes to support to `nr`.
.. option:: --server=args
.. option:: --client=hostname
- Instead of running the jobs locally, send and run them on the given host or
- set of hosts. See `Client/Server`_ section.
+ Instead of running the jobs locally, send and run them on the given `hostname`
+ or set of `hostname`s. See `Client/Server`_ section.
.. option:: --remote-config=file
- Tell fio server to load this local file.
+ Tell fio server to load this local `file`.
.. option:: --idle-prof=option
.. option:: --inflate-log=log
- Inflate and output compressed log.
+ Inflate and output compressed `log`.
.. option:: --trigger-file=file
- Execute trigger cmd when file exists.
+ Execute trigger command when `file` exists.
-.. option:: --trigger-timeout=t
+.. option:: --trigger-timeout=time
- Execute trigger at this time.
+ Execute trigger at this `time`.
-.. option:: --trigger=cmd
+.. option:: --trigger=command
- Set this command as local trigger.
+ Set this `command` as local trigger.
-.. option:: --trigger-remote=cmd
+.. option:: --trigger-remote=command
- Set this command as remote trigger.
+ Set this `command` as remote trigger.
.. option:: --aux-path=path
- Use this path for fio state generated files.
+ Use this `path` for fio state generated files.
Any parameters following the options will be assumed to be job files, unless
they match a job file parameter. Multiple job files can be listed and each job
*global* sections if so desired. A job is only affected by a *global* section
residing above it.
-The :option:`--cmdhelp` option also lists all options. If used with an `option`
-argument, :option:`--cmdhelp` will detail the given `option`.
+The :option:`--cmdhelp` option also lists all options. If used with a `command`
+argument, :option:`--cmdhelp` will detail the given `command`.
See the `examples/` directory for inspiration on how to write job files. Note
the copyright and license requirements currently apply to `examples/` files.
prefixes. To specify power-of-10 decimal values defined in the
International System of Units (SI):
- * *Ki* -- means kilo (K) or 1000
- * *Mi* -- means mega (M) or 1000**2
- * *Gi* -- means giga (G) or 1000**3
- * *Ti* -- means tera (T) or 1000**4
- * *Pi* -- means peta (P) or 1000**5
+ * *K* -- means kilo (K) or 1000
+ * *M* -- means mega (M) or 1000**2
+ * *G* -- means giga (G) or 1000**3
+ * *T* -- means tera (T) or 1000**4
+ * *P* -- means peta (P) or 1000**5
To specify power-of-2 binary values defined in IEC 80000-13:
- * *K* -- means kibi (Ki) or 1024
- * *M* -- means mebi (Mi) or 1024**2
- * *G* -- means gibi (Gi) or 1024**3
- * *T* -- means tebi (Ti) or 1024**4
- * *P* -- means pebi (Pi) or 1024**5
+ * *Ki* -- means kibi (Ki) or 1024
+ * *Mi* -- means mebi (Mi) or 1024**2
+ * *Gi* -- means gibi (Gi) or 1024**3
+ * *Ti* -- means tebi (Ti) or 1024**4
+ * *Pi* -- means pebi (Pi) or 1024**5
With :option:`kb_base`\=1024 (the default), the unit prefixes are opposite
from those specified in the SI and IEC 80000-13 standards to provide
**sequential**
Finish one file before moving on to the next. Multiple files can
- still be open depending on 'openfiles'.
+ still be open depending on :option:`openfiles`.
**zipf**
Use a *Zipf* distribution to decide what file to access.
.. option:: direct=bool
If value is true, use non-buffered I/O. This is usually O_DIRECT. Note that
- ZFS on Solaris doesn't support direct I/O. On Windows the synchronous
+ OpenBSD and ZFS on Solaris don't support direct I/O. On Windows the synchronous
ioengines don't support direct I/O. Default: false.
.. option:: atomic=bool
Make every `N-th` write a barrier write.
-.. option:: sync_file_range=str:val
+.. option:: sync_file_range=str:int
- Use :manpage:`sync_file_range(2)` for every `val` number of write
+ Use :manpage:`sync_file_range(2)` for every `int` number of write
operations. Fio will track range of writes that have happened since the last
:manpage:`sync_file_range(2)` call. `str` can currently be one or more of:
Zoned random distribution
When using a **zipf** or **pareto** distribution, an input value is also
- needed to define the access pattern. For **zipf**, this is the `zipf
+ needed to define the access pattern. For **zipf**, this is the `Zipf
theta`. For **pareto**, it's the `Pareto power`. Fio includes a test
- program, :command:`genzipf`, that can be used visualize what the given input
+ program, :command:`fio-genzipf`, that can be used visualize what the given input
values will yield in terms of hit rates. If you wanted to use **zipf** with
a `theta` of 1.2, you would use ``random_distribution=zipf:1.2`` as the
option. If a non-uniform model is used, fio will disable use of the random
access that should fall within what range of the file or device. For
example, given a criteria of:
- * 60% of accesses should be to the first 10%
- * 30% of accesses should be to the next 20%
- * 8% of accesses should be to the next 30%
- * 2% of accesses should be to the next 40%
+ * 60% of accesses should be to the first 10%
+ * 30% of accesses should be to the next 20%
+ * 8% of accesses should be to the next 30%
+ * 2% of accesses should be to the next 40%
we can define that through zoning of the random accesses. For the above
example, the user would do::
.. option:: random_generator=str
- Fio supports the following engines for generating
- I/O offsets for random I/O:
+ Fio supports the following engines for generating I/O offsets for random I/O:
**tausworthe**
- Strong 2^88 cycle random number generator
+ Strong 2^88 cycle random number generator.
**lfsr**
- Linear feedback shift register generator
+ Linear feedback shift register generator.
**tausworthe64**
- Strong 64-bit 2^258 cycle random number generator
+ Strong 64-bit 2^258 cycle random number generator.
**tausworthe** is a strong random number generator, but it requires tracking
on the side if we want to ensure that blocks are only read or written
- once. **LFSR** guarantees that we never generate the same offset twice, and
+ once. **lfsr** guarantees that we never generate the same offset twice, and
it's also less computationally expensive. It's not a true random generator,
- however, though for I/O purposes it's typically good enough. **LFSR** only
+ however, though for I/O purposes it's typically good enough. **lfsr** only
works with single block sizes, not with workloads that use multiple block
sizes. If used with such a workload, fio may read or write some blocks
multiple times. The default value is **tausworthe**, unless the required
**cudamalloc**
Use GPU memory as the buffers for GPUDirect RDMA benchmark.
- The ioengine must be rdma.
+ The :option:`ioengine` must be `rdma`.
The area allocated is a function of the maximum allowed bs size for the job,
multiplied by the I/O depth given. Note that for **shmhuge** and
should point there. So if it's mounted in :file:`/huge`, you would use
`mem=mmaphuge:/huge/somefile`.
-.. option:: iomem_align=int
+.. option:: iomem_align=int, mem_align=int
This indicates the memory alignment of the I/O memory buffers. Note that
the given alignment is applied to the first I/O unit buffer, if using
SCSI generic sg v3 I/O. May either be synchronous using the SG_IO
ioctl, or if the target is an sg character device we use
:manpage:`read(2)` and :manpage:`write(2)` for asynchronous
- I/O. Requires filename option to specify either block or character
- devices.
+ I/O. Requires :option:`filename` option to specify either block or
+ character devices.
**null**
Doesn't transfer any data, just pretends to. This is mainly used to
Doesn't transfer any data, but burns CPU cycles according to the
:option:`cpuload` and :option:`cpuchunks` options. Setting
:option:`cpuload`\=85 will cause that job to do nothing but burn 85%
- of the CPU. In case of SMP machines, use :option:`numjobs`
- =<no_of_cpu> to get desired CPU usage, as the cpuload only loads a
+ of the CPU. In case of SMP machines, use :option:`numjobs`=<nr_of_cpu>
+ to get desired CPU usage, as the cpuload only loads a
single CPU at the desired rate. A job never finishes unless there is
at least one non-cpuio job.
**ftruncate**
I/O engine that sends :manpage:`ftruncate(2)` operations in response
to write (DDIR_WRITE) events. Each ftruncate issued sets the file's
- size to the current block offset. Block size is ignored.
+ size to the current block offset. :option:`blocksize` is ignored.
**e4defrag**
I/O engine that does regular EXT4_IOC_MOVE_EXT ioctls to simulate
defines engine specific options.
**libhdfs**
- Read and write through Hadoop (HDFS). The :file:`filename` option
+ Read and write through Hadoop (HDFS). The :option:`filename` option
is used to specify host,port of the hdfs name-node to connect. This
engine interprets offsets a little differently. In HDFS, files once
created cannot be modified so random writes are not possible. To
**external**
Prefix to specify loading an external I/O engine object file. Append
the engine filename, e.g. ``ioengine=external:/tmp/foo.o`` to load
- ioengine :file:`foo.o` in :file:`/tmp`.
+ ioengine :file:`foo.o` in :file:`/tmp`. The path can be either
+ absolute or relative. See :file:`engines/skeleton_external.c` for
+ details of writing an external I/O engine.
I/O engine specific parameters
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In addition, there are some parameters which are only valid when a specific
-ioengine is in use. These are used identically to normal parameters, with the
-caveat that when used on the command line, they must come after the
+:option:`ioengine` is in use. These are used identically to normal parameters,
+with the caveat that when used on the command line, they must come after the
:option:`ioengine` that defines them is selected.
.. option:: userspace_reap : [libaio]
.. option:: hipri_percentage : [pvsync2]
- When hipri is set this determines the probability of a pvsync2 IO being high
+ When hipri is set this determines the probability of a pvsync2 I/O being high
priority. The default is 100%.
.. option:: cpuload=int : [cpuio]
Detect when I/O threads are done, then exit.
-.. option:: hostname=str : [netsplice] [net]
-
- The hostname or IP address to use for TCP or UDP based I/O. If the job is
- a TCP listener or UDP reader, the hostname is not used and must be omitted
- unless it is a valid UDP multicast address.
-
.. option:: namenode=str : [libhdfs]
The hostname or IP address of a HDFS cluster namenode to contact.
.. option:: port=int
+ [libhdfs]
+
+ The listening port of the HFDS cluster namenode.
+
[netsplice], [net]
The TCP or UDP port to bind to or connect to. If this is used with
this will be the starting port number since fio will use a range of
ports.
- [libhdfs]
+.. option:: hostname=str : [netsplice] [net]
- The listening port of the HFDS cluster namenode.
+ The hostname or IP address to use for TCP or UDP based I/O. If the job is
+ a TCP listener or UDP reader, the hostname is not used and must be omitted
+ unless it is a valid UDP multicast address.
.. option:: interface=str : [netsplice] [net]
Set TCP_NODELAY on TCP connections.
-.. option:: protocol=str : [netsplice] [net]
-
-.. option:: proto=str : [netsplice] [net]
+.. option:: protocol=str, proto=str : [netsplice] [net]
The network protocol to use. Accepted values are:
When the protocol is TCP or UDP, the port must also be given, as well as the
hostname if the job is a TCP listener or UDP reader. For unix sockets, the
- normal filename option should be used and the port is invalid.
+ normal :option:`filename` option should be used and the port is invalid.
.. option:: listen : [netsplice] [net]
.. option:: thinktime_blocks=int
Only valid if :option:`thinktime` is set - control how many blocks to issue,
- before waiting `thinktime` usecs. If not set, defaults to 1 which will make
- fio wait `thinktime` usecs after every block. This effectively makes any
+ before waiting :option:`thinktime` usecs. If not set, defaults to 1 which will make
+ fio wait :option:`thinktime` usecs after every block. This effectively makes any
queue depth setting redundant, since no more than 1 I/O will be queued
- before we have to complete it and do our thinktime. In other words, this
+ before we have to complete it and do our :option:`thinktime`. In other words, this
setting effectively caps the queue depth if the latter is larger.
.. option:: rate=int[,int][,int]
state is loaded for the verify read phase. The format of the filename is,
roughly::
- <type>-<jobname>-<jobindex>-verify.state.
+ <type>-<jobname>-<jobindex>-verify.state.
<type> is "local" for a local run, "sock" for a client/server socket
connection, and "ip" (192.168.0.1, for instance) for a networked
write_lat_log=foo
The actual log names will be :file:`foo_slat.x.log`, :file:`foo_clat.x.log`,
- and :file:`foo_lat.x.log`, where `x` is the index of the job (1..N, where N
- is the number of jobs). This helps :command:`fio_generate_plot` find the
+ and :file:`foo_lat.x.log`, where `x` is the index of the job (`1..N`, where `N`
+ is the number of jobs). This helps :command:`fio_generate_plots` find the
logs automatically. If :option:`per_job_logs` is false, then the filename
will not include the job index. See `Log File Formats`_.
Same as :option:`write_lat_log`, but writes I/O completion latency
histograms. If no filename is given with this option, the default filename
of :file:`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,
+ 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 :option:`per_job_logs` is false,
then the filename will not include the job index. See `Log File Formats`_.
Same as :option:`write_bw_log`, but writes IOPS. If no filename is given
with this option, the default filename of :file:`jobname_type.x.log` is
- used,where `x` is the index of the job (1..N, where `N` is the number of
+ 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 :option:`per_job_logs` is false, then the filename will not include
the job index. See `Log File Formats`_.
.. option:: disable_slat=bool
Disable measurements of submission latency numbers. See
- :option:`disable_slat`.
+ :option:`disable_lat`.
.. option:: disable_bw_measurement=bool, disable_bw=bool
.. option:: clat_percentiles=bool
- Enable the reporting of percentiles of completion latencies.
+ Enable the reporting of percentiles of completion latencies. This
+ option is mutually exclusive with :option:`lat_percentiles`.
+
+.. option:: lat_percentiles=bool
+
+ Enable the reporting of percentiles of IO latencies. This is similar
+ to :option:`clat_percentiles`, except that this includes the
+ submission latency. This option is mutually exclusive with
+ :option:`clat_percentiles`.
.. option:: percentile_list=float_list
To view a profile's additional options use :option:`--cmdhelp` after specifying
the profile. For example::
-$ fio --profile=act --cmdhelp
+ $ fio --profile=act --cmdhelp
Act profile options
~~~~~~~~~~~~~~~~~~~
.. option:: threads-per-queue=int
:noindex:
- Number of read IO threads per device. Default: 8.
+ Number of read I/O threads per device. Default: 8.
.. option:: read-req-num-512-blocks=int
:noindex:
.. option:: size=str
:noindex:
- Size in MiB
+ Size in MiB.
.. option:: block=int
:noindex:
The other values are fairly self explanatory -- number of threads currently
running and doing I/O, the number of currently open files (f=), the estimated
completion percentage, the rate of I/O since last check (read speed listed first,
-then write speed and optionally trim speed) in terms of bandwidth and IOPS, and time to completion for the current
-running group. It's impossible to estimate runtime of the following groups (if
-any).
+then write speed and optionally trim speed) in terms of bandwidth and IOPS,
+and time to completion for the current running group. It's impossible to estimate
+runtime of the following groups (if any).
..
Example output was based on the following:
**run**
The smallest and longest runtimes of the threads in this group.
-And finally, the disk statistics are printed. They will look like this::
+And finally, the disk statistics are printed. This is Linux specific. They will look like this::
Disk stats (read/write):
sda: ios=16398/16511, merge=30/162, ticks=6853/819634, in_queue=826487, util=100.00%
::
- terse version, fio version [v3], jobname, groupid, error
+ terse version, fio version [v3], jobname, groupid, error
READ status::
Completion latency: min, max, mean, stdev (usec)
Completion latency percentiles: 20 fields (see below)
Total latency: min, max, mean, stdev (usec)
- Bw (KiB/s): min, max, aggregate percentage of total, mean, stdev, number of samples [v5]
- IOPS [v5]: min, max, mean, stdev, number of samples
+ Bw (KiB/s): min, max, aggregate percentage of total, mean, stdev, number of samples [v5]
+ IOPS [v5]: min, max, mean, stdev, number of samples
WRITE status:
Completion latency: min, max, mean, stdev (usec)
Completion latency percentiles: 20 fields (see below)
Total latency: min, max, mean, stdev (usec)
- Bw (KiB/s): min, max, aggregate percentage of total, mean, stdev, number of samples [v5]
- IOPS [v5]: min, max, mean, stdev, number of samples
+ Bw (KiB/s): min, max, aggregate percentage of total, mean, stdev, number of samples [v5]
+ IOPS [v5]: min, max, mean, stdev, number of samples
TRIM status [all but version 3]:
- Fields are similar to READ/WRITE status.
+ Fields are similar to READ/WRITE status.
CPU usage::
Disk utilization [v3]::
- Disk name, Read ios, write ios,
- Read merges, write merges,
- Read ticks, write ticks,
- Time spent in queue, disk utilization percentage
+ disk name, read ios, write ios, read merges, write merges, read ticks, write ticks,
+ time spent in queue, disk utilization percentage
Additional Info (dependent on continue_on_error, default off)::
Completion latency percentiles can be a grouping of up to 20 sets, so for the
terse output fio writes all of them. Each field will look like this::
- 1.00%=6112
+ 1.00%=6112
which is the Xth percentile, and the `usec` latency associated with it.
-For disk utilization, all disks used by fio are shown. So for each disk there
+For `Disk utilization`, all disks used by fio are shown. So for each disk there
will be a disk utilization section.
Below is a single line containing short names for each of the fields in the
minimal output v3, separated by semicolons::
- 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_min;read_clat_max;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_min;write_clat_max;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;cpu_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
+ 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_min;read_clat_max;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_min;write_clat_max;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;cpu_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
+
+
+JSON output
+------------
+
+The `json` output format is intended to be both human readable and convenient
+for automated parsing. For the most part its sections mirror those of the
+`normal` output. The `runtime` value is reported in msec and the `bw` value is
+reported in 1024 bytes per second units.
JSON+ output
json+ output and generates CSV-formatted latency data suitable for plotting.
The latency durations actually represent the midpoints of latency intervals.
-For details refer to stat.h.
+For details refer to :file:`stat.h`.
Trace file format
rw, offset, length
-where `rw=0/1` for read/write, and the offset and length entries being in bytes.
+where `rw=0/1` for read/write, and the `offset` and `length` entries being in bytes.
This format is not supported in fio versions >= 1.20-rc3.
filename action
-The filename is given as an absolute path. The action can be one of these:
+The `filename` is given as an absolute path. The `action` can be one of these:
**add**
- Add the given filename to the trace.
+ Add the given `filename` to the trace.
**open**
- Open the file with the given filename. The filename has to have
+ Open the file with the given `filename`. The `filename` has to have
been added with the **add** action before.
**close**
- Close the file with the given filename. The file has to have been
+ Close the file with the given `filename`. The file has to have been
opened before.
Verification trigger example
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Let's say we want to run a powercut test on the remote machine 'server'. Our
-write workload is in :file:`write-test.fio`. We want to cut power to 'server' at
+Let's say we want to run a powercut test on the remote Linux machine 'server'.
+Our write workload is in :file:`write-test.fio`. We want to cut power to 'server' at
some point during the run, and we'll run this test from the safety or our local
machine, 'localbox'. On the server, we'll start the fio backend normally::
on the type of log, it will be one of the following:
**Latency log**
- Value is latency in usecs
+ Value is latency in nsecs
**Bandwidth log**
Value is in KiB/sec
**IOPS log**
Start the server on the machine which has access to the storage DUT::
- fio --server=args
+ $ fio --server=args
where `args` defines what fio listens to. The arguments are of the form
``type,hostname`` or ``IP,port``. *type* is either ``ip`` (or ip4) for TCP/IP
projects / fio.git / blobdiff