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
$ fio --name=random-writers --ioengine=libaio --iodepth=4 --rw=randwrite --bs=32k --direct=0 --size=64m --numjobs=4
+When fio is utilized as a basis of any reasonably large test suite, it might be
+desirable to share a set of standardized settings across multiple job files.
+Instead of copy/pasting such settings, any section may pull in an external
+.fio file with 'include filename' directive, as in the following example:
+
+; -- start job file including.fio --
+[global]
+filename=/tmp/test
+filesize=1m
+include glob-include.fio
+
+[test]
+rw=randread
+bs=4k
+time_based=1
+runtime=10
+include test-include.fio
+; -- end job file including.fio --
+
+; -- start job file glob-include.fio --
+thread=1
+group_reporting=1
+; -- end job file glob-include.fio --
+
+; -- start job file test-include.fio --
+ioengine=libaio
+iodepth=4
+; -- end job file test-include.fio --
+
+Settings pulled into a section apply to that section only (except global
+section). Include directives may be nested in that any included file may
+contain further include directive(s). Include files may not contain []
+sections.
+
+
4.1 Environment variables
-------------------------
str String. This is a sequence of alpha characters.
time Integer with possible time suffix. In seconds unless otherwise
specified, use eg 10m for 10 minutes. Accepts s/m/h for seconds,
- minutes, and hours.
+ minutes, and hours, and accepts 'ms' (or 'msec') for milliseconds,
+ and 'us' (or 'usec') for microseconds.
int SI integer. A whole number value, which may contain a suffix
describing the base of the number. Accepted suffixes are k/m/g/t/p,
meaning kilo, mega, giga, tera, and peta. The suffix is not case
not parsed.
directory=str Prefix filenames with this directory. Used to place files
- in a different location than "./".
+ in a different location than "./". See the 'filename' option
+ for escaping certain characters.
filename=str Fio normally makes up a filename based on the job name,
thread number, and file number. If you want to share
randrepeat=bool For random IO workloads, seed the generator in a predictable
way so that results are repeatable across repetitions.
+randseed=int Seed the random number generators based on this seed value, to
+ be able to control what sequence of output is being generated.
+ If not set, the random sequence depends on the randrepeat
+ setting.
+
use_os_rand=bool Fio can either use the random generator supplied by the OS
to generator random offsets, or it can use it's own internal
generator (based on Tausworthe). Default is to use the
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
+ means that the 'size' option sets both the region and size of
+ IO to be performed. Sometimes that is not what you want. With
+ this option, it is possible to define just the amount of IO
+ that fio should do. For instance, if 'size' is set to 20G and
+ 'io_limit' is set to 5G, fio will perform IO within the first
+ 20G but exit when 5G have been done.
+
filesize=int Individual file sizes. May be a range, in which case fio
will select sizes for files at random within the given range
and limited to 'size' in total (if that is given). If not
given, each created file is the same size.
+file_append=bool Perform IO after the end of the file. Normally fio will
+ operate within the size of a file. If this option is set, then
+ fio will append to the file instead. This has identical
+ behavior to setting offset to the size of a file. This option
+ is ignored on non-regular files.
+
fill_device=bool
fill_fs=bool Sets size to something really large and waits for ENOSPC (no
space left on device) as the terminating condition. Only makes
zero_buffers If this option is given, fio will init the IO buffers to
all zeroes. The default is to fill them with random data.
+ The resulting IO buffers will not be completely zeroed,
+ unless scramble_buffers is also turned off.
refill_buffers If this option is given, fio will refill the IO buffers
on every submit. The default is to only fill it at init
alternate random and zeroed data throughout the IO
buffer.
+buffer_pattern=str 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 "".
+
+dedupe_percentage=int If set, fio will generate this percentage of
+ identical buffers when writing. These buffers will be
+ naturally dedupable. The contents of the buffers depend on
+ what other buffer compression settings have been set. It's
+ possible to have the individual buffers either fully
+ compressible, or not at all. This option only controls the
+ distribution of unique buffers.
+
nrfiles=int Number of files to use for this job. Defaults to 1.
openfiles=int Number of files to keep open at the same time. Defaults to
channel semantics (Send/Recv) for the
InfiniBand, RoCE and iWARP protocols.
- falloc IO engine that does regular fallocate to
- simulate data transfer as fio ioengine.
- DDIR_READ does fallocate(,mode = keep_size,)
- DDIR_WRITE does fallocate(,mode = 0)
- DDIR_TRIM does fallocate(,mode = punch_hole)
+ falloc IO engine that does regular fallocate to
+ simulate data transfer as fio ioengine.
+ DDIR_READ does fallocate(,mode = keep_size,)
+ DDIR_WRITE does fallocate(,mode = 0)
+ DDIR_TRIM does fallocate(,mode = punch_hole)
e4defrag IO engine that does regular EXT4_IOC_MOVE_EXT
- ioctls to simulate defragment activity in
- request to DDIR_WRITE event
+ ioctls to simulate defragment activity in
+ request to DDIR_WRITE event
+
+ rbd IO engine supporting direct access to Ceph
+ Rados Block Devices (RBD) via librbd without
+ the need to use the kernel rbd driver. This
+ ioengine defines engine specific options.
+
+ gfapi Using Glusterfs libgfapi sync interface to
+ direct access to Glusterfs volumes without
+ options.
+
+ gfapi_async Using Glusterfs libgfapi async interface
+ to direct access to Glusterfs volumes without
+ having to go through FUSE. This ioengine
+ defines engine specific options.
+
+ libhdfs Read and write through Hadoop (HDFS).
+ The '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 imitate this, libhdfs engine
+ expects bunch of small files to be created
+ over HDFS, and engine will randomly pick a
+ file out of those files based on the offset
+ generated by fio backend. (see the example
+ job file to create such files, use rw=write
+ option). Please note, you might want to set
+ necessary environment variables to work with
+ hdfs/libhdfs properly.
external Prefix to specify loading an external
IO engine object file. Append the engine
O_DIRECT. Note that ZFS on Solaris doesn't support direct io.
On Windows the synchronous ioengines don't support direct io.
+atomic=bool If value is true, attempt to use atomic direct IO. Atomic
+ writes are guaranteed to be stable once acknowledged by
+ the operating system. Only Linux supports O_ATOMIC right
+ now.
+
buffered=bool If value is true, use buffered io. This is the opposite
of the 'direct' option. Defaults to true.
caps the file size at real_size - offset.
offset_increment=int If this is provided, then the real offset becomes
- the offset + offset_increment * thread_number, where the
- thread number is a counter that starts at 0 and is incremented
- for each job. This option is useful if there are several jobs
- which are intended to operate on a file in parallel in disjoint
- segments, with even spacing between the starting points.
+ offset + offset_increment * thread_number, where the thread
+ number is a counter that starts at 0 and is incremented for
+ each sub-job (i.e. when numjobs option is specified). This
+ option is useful if there are several jobs which are intended
+ to operate on a file in parallel disjoint segments, with
+ even spacing between the starting points.
number_ios=int Fio will normally perform IOs until it has exhausted the size
of the region set by size=, or if it exhaust the allocated
the job to exit. The same format as rate is used for read vs
write separation.
+latency_target=int If set, fio will attempt to find the max performance
+ point that the given workload will run at while maintaining a
+ latency below this target. The values is given in microseconds.
+ See latency_window and latency_percentile
+
+latency_window=int Used with latency_target to specify the sample window
+ that the job is run at varying queue depths to test the
+ performance. The value is given in microseconds.
+
+latency_percentile=float The percentage of IOs that must fall within the
+ criteria specified by latency_target and latency_window. If not
+ set, this defaults to 100.0, meaning that all IOs must be equal
+ or below to the value set by latency_target.
+
max_latency=int If set, fio will exit the job if it exceeds this maximum
latency. It will exit with an ETIME error.
allows a range of CPUs. Say you wanted a binding to CPUs
1, 5, and 8-15, you would set cpus_allowed=1,5,8-15.
+cpus_allowed_policy=str Set the policy of how fio distributes the CPUs
+ specified by cpus_allowed or cpumask. Two policies are
+ supported:
+
+ shared All jobs will share the CPU set specified.
+ split Each job will get a unique CPU from the CPU set.
+
+ 'shared' is the default behaviour, if the option isn't
+ specified. If split is specified, then fio will will assign
+ one cpu per job. If not enough CPUs are given for the jobs
+ listed, then fio will roundrobin the CPUs in the set.
+
numa_cpu_nodes=str Set this job running on spcified NUMA nodes' CPUs. The
arguments allow comma delimited list of cpu numbers,
A-B ranges, or 'all'. Note, to enable numa options support,
to repeat the same workload a given number of times. Defaults
to 1.
+verify_only Do not perform specified workload---only verify data still
+ matches previous invocation of this workload. This option
+ allows one to check data multiple times at a later date
+ without overwriting it. This option makes sense only for
+ workloads that write data, and does not support workloads
+ with the time_based option set.
+
do_verify=bool Run the verify phase after a write phase. Only makes sense if
verify is set. Defaults to 1.
crc7 Use a crc7 sum of the data area and store
it in the header of each block.
+ xxhash Use xxhash as the checksum function. Generally
+ the fastest software checksum that fio
+ supports.
+
sha512 Use sha512 as the checksum function.
sha256 Use sha256 as the checksum function.
meta Write extra information about each io
(timestamp, block number etc.). The block
- number is verified. See also verify_pattern.
+ number is verified. The io sequence number is
+ verified for workloads that write data.
+ See also verify_pattern.
null Only pretend to verify. Useful for testing
internals with ioengine=null, not for much
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.
[cpu] cpuchunks=int Split the load into cycles of the given time. In
microseconds.
+[cpu] exit_on_io_done=bool Detect when IO threads are done, then exit.
+
[netsplice] hostname=str
[net] hostname=str The host name or IP address to use for TCP or UDP based IO.
If the job is a TCP listener or UDP reader, the hostname is not
[net] proto=str The network protocol to use. Accepted values are:
tcp Transmission control protocol
+ tcpv6 Transmission control protocol V6
udp User datagram protocol
+ udpv6 User datagram protocol V6
unix UNIX domain socket
When the protocol is TCP or UDP, the port must also be given,
M Running, doing mixed sequential reads/writes.
m Running, doing mixed random reads/writes.
F Running, currently waiting for fsync()
+ f Running, finishing up (writing IO logs, etc)
V Running, doing verification of written data.
E Thread exited, not reaped by main thread yet.
_ Thread reaped, or
X Thread reaped, exited with an error.
K Thread reaped, exited due to signal.
+Fio will condense the thread string as not to take up more space on the
+command line as is needed. For instance, if you have 10 readers and 10
+writers running, the output would look like this:
+
+Jobs: 20 (f=20): [R(10),W(10)] [4.0% done] [2103MB/0KB/0KB /s] [538K/0/0 iops] [eta 57m:36s]
+
+Fio will still maintain the ordering, though. So the above means that jobs
+1..10 are readers, and 11..20 are writers.
+
The other values are fairly self explanatory - number of threads
currently running and doing io, rate of io since last check (read speed
listed first, then write speed), and the estimated completion percentage
projects / fio.git / blobdiff