section residing above it. If the first character in a line is a ';' or a
'#', the entire line is discarded as a comment.
-So lets look at a really simple job file that define to threads, each
+So let's look at a really simple job file that defines two processes, each
randomly reading from a 128MiB file.
; -- start job file --
$ fio --name=global --rw=randread --size=128m --name=job1 --name=job2
-Lets look at an example that have a number of processes writing randomly
+Let's look at an example that has a number of processes writing randomly
to files.
; -- start job file --
$ fio --name=random-writers --ioengine=libaio --iodepth=4 --rw=randwrite --bs=32k --direct=0 --size=64m --numjobs=4
+fio also supports environment variable expansion in job files. Any
+substring of the form "${VARNAME}" as part of an option value (in other
+words, on the right of the `='), will be expanded to the value of the
+environment variable called VARNAME. If no such environment variable
+is defined, or VARNAME is the empty string, the empty string will be
+substituted.
+
+As an example, let's look at a sample fio invocation and job file:
+
+$ SIZE=64m NUMJOBS=4 fio jobfile.fio
+
+; -- start job file --
+[random-writers]
+rw=randwrite
+size=${SIZE}
+numjobs=${NUMJOBS}
+; -- end job file --
+
+This will expand to the following equivalent job file at runtime:
+
+; -- start job file --
+[random-writers]
+rw=randwrite
+size=64m
+numjobs=4
+; -- end job file --
+
fio ships with a few example job files, you can also look there for
inspiration.
a string. The following types are used:
str String. This is a sequence of alpha characters.
-int Integer. A whole number value, may be negative.
-siint SI integer. A whole number value, which may contain a postfix
+time Integer with possible time postfix. In seconds unless otherwise
+ specified, use eg 10m for 10 minutes. Accepts s/m/h for seconds,
+ minutes, and hours.
+int SI integer. A whole number value, which may contain a postfix
describing the base of the number. Accepted postfixes are k/m/g,
meaning kilo, mega, and giga. So if you want to specify 4096,
you could either write out '4096' or just give 4k. The postfixes
signify base 2 values, so 1024 is 1k and 1024k is 1m and so on.
If the option accepts an upper and lower range, use a colon ':'
- or minus '-' to seperate such values. See irange.
+ or minus '-' to separate such values. May also include a prefix
+ to indicate numbers base. If 0x is used, the number is assumed to
+ be hexadecimal. See irange.
bool Boolean. Usually parsed as an integer, however only defined for
true and false (1 and 0).
irange Integer range with postfix. Allows value range to be given, such
- as 1024-4096. A colon may also be used as the seperator, eg
+ as 1024-4096. A colon may also be used as the separator, eg
1k:4k. If the option allows two sets of ranges, they can be
specified with a ',' or '/' delimiter: 1k-4k/8k-32k. Also see
- siint.
+ int.
With the above in mind, here follows the complete list of fio job
parameters.
dump this text description when this job is run. It's
not parsed.
-directory=str Prefix filenames with this directory. Used to places files
+directory=str Prefix filenames with this directory. Used to place files
in a different location than "./".
filename=str Fio normally makes up a filename based on the job name,
thread number, and file number. If you want to share
files between threads in a job or several jobs, specify
a filename for each of them to override the default. If
- the ioengine used is 'net', the filename is the host and
- port to connect to in the format of =host/port. If the
- ioengine is file based, you can specify a number of files
- by seperating the names with a ':' colon. So if you wanted
- a job to open /dev/sda and /dev/sdb as the two working files,
- you would use filename=/dev/sda:/dev/sdb. '-' is a reserved
- name, meaning stdin or stdout. Which of the two depends
- on the read/write direction set.
+ the ioengine used is 'net', the filename is the host, port,
+ and protocol to use in the format of =host/port/protocol.
+ See ioengine=net for more. If the ioengine is file based, you
+ can specify a number of files by separating the names with a
+ ':' colon. So if you wanted a job to open /dev/sda and /dev/sdb
+ as the two working files, you would use
+ filename=/dev/sda:/dev/sdb. '-' is a reserved name, meaning
+ stdin or stdout. Which of the two depends on the read/write
+ direction set.
opendir=str Tell fio to recursively add any file it can find in this
directory and down the file system tree.
+lockfile=str Fio defaults to not locking any files before it does
+ IO to them. If a file or file descriptor is shared, fio
+ can serialize IO to that file to make the end result
+ consistent. This is usual for emulating real workloads that
+ share files. The lock modes are:
+
+ none No locking. The default.
+ exclusive Only one thread/process may do IO,
+ excluding all others.
+ readwrite Read-write locking on the file. Many
+ readers may access the file at the
+ same time, but writes get exclusive
+ access.
+
+ The option may be post-fixed with a lock batch number. If
+ set, then each thread/process may do that amount of IOs to
+ the file before giving up the lock. Since lock acquisition is
+ expensive, batching the lock/unlocks will speed up IO.
+
readwrite=str
rw=str Type of io pattern. Accepted values are:
If set, fio will use POSIX_FADV_SEQUENTIAL for sequential
IO and POSIX_FADV_RANDOM for random IO.
-size=siint The total size of file io for this job. This may describe
- the size of the single file the job uses, or it may be
- divided between the number of files in the job. If the
- file already exists, the file size will be adjusted to this
- size if larger than the current file size. If this parameter
- is not given and the file exists, the file size will be used.
+size=int The total size of file io for this job. Fio will run until
+ this many bytes has been transferred, unless runtime is
+ limited by other options (such as 'runtime', for instance).
+ Unless specific nrfiles and filesize options are given,
+ fio will divide this size between the available files
+ specified by the job.
-filesize=siint Individual file sizes. May be a range, in which case fio
+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.
-blocksize=siint
-bs=siint The block size used for the io units. Defaults to 4k. Values
- can be given for both read and writes. If a single siint is
- given, it will apply to both. If a second siint is specified
+fill_device=bool Sets size to something really large and waits for ENOSPC (no
+ space left on device) as the terminating condition. Only makes
+ sense with sequential write.
+
+blocksize=int
+bs=int The block size used for the io units. Defaults to 4k. Values
+ can be given for both read and writes. If a single int is
+ given, it will apply to both. If a second int is specified
after a comma, it will apply to writes only. In other words,
the format is either bs=read_and_write or bs=read,write.
bs=4k,8k will thus use 4k blocks for reads, and 8k blocks
can do so by passing an empty read size - bs=,8k will set
8k for writes and leave the read default value.
+blockalign=int
+ba=int At what boundary to align random IO offsets. Defaults to
+ the same as 'blocksize' the minimum blocksize given.
+ Minimum alignment is typically 512b for using direct IO,
+ though it usually depends on the hardware block size. This
+ option is mutually exclusive with using a random map for
+ files, so it will turn off that option.
+
blocksize_range=irange
bsrange=irange Instead of giving a single block size, specify a range
and fio will mix the issued io block sizes. The issued
writes, however a second range can be given after a comma.
See bs=.
+bssplit=str Sometimes you want even finer grained control of the
+ block sizes issued, not just an even split between them.
+ This option allows you to weight various block sizes,
+ so that you are able to define a specific amount of
+ block sizes issued. The format for this option is:
+
+ bssplit=blocksize/percentage:blocksize/percentage
+
+ for as many block sizes as needed. So if you want to define
+ a workload that has 50% 64k blocks, 10% 4k blocks, and
+ 40% 32k blocks, you would write:
+
+ bssplit=4k/10:64k/50:32k/40
+
+ Ordering does not matter. If the percentage is left blank,
+ fio will fill in the remaining values evenly. So a bssplit
+ option like this one:
+
+ bssplit=4k/50:1k/:32k/
+
+ would have 50% 4k ios, and 25% 1k and 32k ios. The percentages
+ always add up to 100, if bssplit is given a range that adds
+ up to more, it will error out.
+
+ bssplit also supports giving separate splits to reads and
+ writes. The format is identical to what bs= accepts. You
+ have to separate the read and write parts with a comma. So
+ if you want a workload that has 50% 2k reads and 50% 4k reads,
+ while having 90% 4k writes and 10% 8k writes, you would
+ specify:
+
+ bssplit=2k/50:4k/50,4k/90,8k/10
+
blocksize_unaligned
bs_unaligned If this option is given, any byte size value within bsrange
may be used as a block range. This typically wont work with
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.
+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
+ time and reuse that data. Only makes sense if zero_buffers
+ isn't specified, naturally. If data verification is enabled,
+ refill_buffers is also automatically enabled.
+
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
roundrobin Round robin over open files. This
is the default.
+ sequential Finish one file before moving on to
+ the next. Multiple files can still be
+ open depending on 'openfiles'.
+
The string can have a number appended, indicating how
often to switch to a new file. So if option random:4 is
given, fio will switch to a new random file after 4 ios
sync Basic read(2) or write(2) io. lseek(2) is
used to position the io location.
- libaio Linux native asynchronous io.
+ psync Basic pread(2) or pwrite(2) io.
+
+ vsync Basic readv(2) or writev(2) IO.
+
+ libaio Linux native asynchronous io. Note that Linux
+ may only support queued behaviour with
+ non-buffered IO (set direct=1 or buffered=0).
posixaio glibc posix asynchronous io.
+ solarisaio Solaris native asynchronous io.
+
mmap File is memory mapped and data copied
to/from using memcpy(3).
net Transfer over the network to given host:port.
'filename' must be set appropriately to
- filename=host/port regardless of send
+ filename=host/port/protocol regardless of send
or receive, if the latter only the port
- argument is used.
+ argument is used. 'host' may be an IP address
+ or hostname, port is the port number to be used,
+ and protocol may be 'udp' or 'tcp'. If no
+ protocol is given, TCP is used.
- cpu Doesn't transfer any data, but burns CPU
+ netsplice Like net, but uses splice/vmsplice to
+ map data and send/receive.
+
+ cpuio Doesn't transfer any data, but burns CPU
cycles according to the cpuload= and
cpucycle= options. Setting cpuload=85
will cause that job to do nothing but burn
- 85% of the CPU.
+ 85% of the CPU. In case of SMP machines,
+ use numjobs=<no_of_cpu> to get desired CPU
+ usage, as the cpuload only loads a single
+ CPU at the desired rate.
guasi The GUASI IO engine is the Generic Userspace
Asyncronous Syscall Interface approach
job, can be overridden with a larger value for higher
concurrency.
+iodepth_batch_submit=int
iodepth_batch=int This defines how many pieces of IO to submit at once.
- It defaults to the same as iodepth, but can be set lower
- if one so desires.
+ It defaults to 1 which means that we submit each IO
+ as soon as it is available, but can be raised to submit
+ bigger batches of IO at the time.
+
+iodepth_batch_complete=int This defines how many pieces of IO to retrieve
+ at once. It defaults to 1 which means that we'll ask
+ for a minimum of 1 IO in the retrieval process from
+ the kernel. The IO retrieval will go on until we
+ hit the limit set by iodepth_low. If this variable is
+ set to 0, then fio will always check for completed
+ events before queuing more IO. This helps reduce
+ IO latency, at the cost of more retrieval system calls.
iodepth_low=int The low water mark indicating when to start filling
the queue again. Defaults to the same as iodepth, meaning
buffered=bool If value is true, use buffered io. This is the opposite
of the 'direct' option. Defaults to true.
-offset=siint Start io at the given offset in the file. The data before
+offset=int Start io at the given offset in the file. The data before
the given offset will not be touched. This effectively
caps the file size at real_size - offset.
not sync the file. The exception is the sg io engine, which
synchronizes the disk cache anyway.
-overwrite=bool If writing to a file, setup the file first and do overwrites.
+overwrite=bool If true, writes to a file will always overwrite existing
+ data. If the file doesn't already exist, it will be
+ created before the write phase begins. If the file exists
+ and is large enough for the specified write phase, nothing
+ will be done.
end_fsync=bool If true, fsync file contents when the job exits.
This differs from end_fsync in that it will happen on every
file close, not just at the end of the job.
-rwmixcycle=int Value in milliseconds describing how often to switch between
- reads and writes for a mixed workload. The default is
- 500 msecs.
-
rwmixread=int How large a percentage of the mix should be reads.
rwmixwrite=int How large a percentage of the mix should be writes. If both
new random offset without looking at past io history. This
means that some blocks may not be read or written, and that
some blocks may be read/written more than once. This option
- is mutually exclusive with verify= for that reason.
+ is mutually exclusive with verify= if and only if multiple
+ blocksizes (via bsrange=) are used, since fio only tracks
+ complete rewrites of blocks.
+
+softrandommap See norandommap. If fio runs with the random block map enabled
+ and it fails to allocate the map, if this option is set it
+ will continue without a random block map. As coverage will
+ not be as complete as with random maps, this option is
+ disabled by default.
nice=int Run the job with the given nice value. See man nice(2).
of milliseconds.
cpumask=int Set the CPU affinity of this job. The parameter given is a
- bitmask of allowed CPU's the job may run on. See man
- sched_setaffinity(2).
-
-startdelay=int Start this job the specified number of seconds after fio
+ bitmask of allowed CPU's the job may run on. So if you want
+ the allowed CPUs to be 1 and 5, you would pass the decimal
+ value of (1 << 1 | 1 << 5), or 34. See man
+ sched_setaffinity(2). This may not work on all supported
+ operating systems or kernel versions. This option doesn't
+ work well for a higher CPU count than what you can store in
+ an integer mask, so it can only control cpus 1-32. For
+ boxes with larger CPU counts, use cpus_allowed.
+
+cpus_allowed=str Controls the same options as cpumask, but it allows a text
+ setting of the permitted CPUs instead. So to use CPUs 1 and
+ 5, you would specify cpus_allowed=1,5. This options also
+ 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.
+
+startdelay=time Start this job the specified number of seconds after fio
has started. Only useful if the job file contains several
jobs, and you want to delay starting some jobs to a certain
time.
-runtime=int Tell fio to terminate processing after the specified number
+runtime=time Tell fio to terminate processing after the specified number
of seconds. It can be quite hard to determine for how long
a specified job will run, so this parameter is handy to
cap the total runtime to a given time.
+time_based If set, fio will run for the duration of the runtime
+ specified even if the file(s) are completely read or
+ written. It will simply loop over the same workload
+ as many times as the runtime allows.
+
+ramp_time=time If set, fio will run the specified workload for this amount
+ of time before logging any performance numbers. Useful for
+ letting performance settle before logging results, thus
+ minimizing the runtime required for stable results. Note
+ that the ramp_time is considered lead in time for a job,
+ thus it will increase the total runtime if a special timeout
+ or runtime is specified.
+
invalidate=bool Invalidate the buffer/page cache parts for this file prior
to starting io. Defaults to true.
location should point there. So if it's mounted in /huge,
you would use mem=mmaphuge:/huge/somefile.
-hugepage-size=siint
+hugepage-size=int
Defines the size of a huge page. Must at least be equal
to the system setting, see /proc/meminfo. Defaults to 4MiB.
Should probably always be a multiple of megabytes, so using
create_fsync=bool fsync the data file after creation. This is the
default.
+create_on_open=bool Don't pre-setup the files for IO, just create open()
+ when it's time to do IO to that file.
+
+pre_read=bool If this is given, files will be pre-read into memory before
+ starting the given IO operation.
+
unlink=bool Unlink the job files when done. Not the default, as repeated
- runs of that job would then waste time recreating the fileset
- again and again.
+ runs of that job would then waste time recreating the file
+ set again and again.
loops=int Run the specified number of iterations of this job. Used
to repeat the same workload a given number of times. Defaults
to 1.
+do_verify=bool Run the verify phase after a write phase. Only makes sense if
+ verify is set. Defaults to 1.
+
verify=str If writing to a file, fio can verify the file contents
after each iteration of the job. The allowed values are:
md5 Use an md5 sum of the data area and store
it in the header of each block.
+ crc64 Use an experimental crc64 sum of the data
+ area and store it in the header of each
+ block.
+
+ crc32c Use a crc32c sum of the data area and store
+ it in the header of each block.
+
+ crc32c-intel Use hardware assisted crc32c calcuation
+ provided on SSE4.2 enabled processors.
+
crc32 Use a crc32 sum of the data area and store
it in the header of each block.
+ crc16 Use a crc16 sum of the data area and store
+ it in the header of each block.
+
+ crc7 Use a crc7 sum of the data area and store
+ it in the header of each block.
+
+ 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.
+
null Only pretend to verify. Useful for testing
internals with ioengine=null, not for much
else.
can ignore this option unless doing huge amounts of really
fast IO where the red-black tree sorting CPU time becomes
significant.
+
+verify_offset=int Swap the verification header with data somewhere else
+ in the block before writing. Its swapped back before
+ verifying.
+
+verify_interval=int Write the verification header at a finer granularity
+ than the blocksize. It will be written for chunks the
+ size of header_interval. blocksize should divide this
+ evenly.
+
+verify_pattern=int If set, fio will fill the io buffers with this
+ pattern. Fio defaults to filling with totally random
+ bytes, but sometimes it's interesting to fill with a known
+ pattern for io verification purposes. Depending on the
+ width of the pattern, fio will fill 1/2/3/4 bytes of the
+ buffer at the time. The verify_pattern cannot be larger than
+ a 32-bit quantity.
+
+verify_fatal=bool Normally fio will keep checking the entire contents
+ before quitting on a block verification failure. If this
+ option is set, fio will exit the job on the first observed
+ failure.
stonewall Wait for preceeding jobs in the job file to exit, before
starting this one. Can be used to insert serialization
new_group Start a new reporting group. If this option isn't given,
jobs in a file will be part of the same reporting group
- unless seperated by a stone wall (or if it's a group
+ unless separated by a stone wall (or if it's a group
by itself, with the numjobs option).
numjobs=int Create the specified number of clones of this job. May be
given, fio will use pthread_create(3) to create threads
instead.
-zonesize=siint Divide a file into zones of the specified size. See zoneskip.
+zonesize=int Divide a file into zones of the specified size. See zoneskip.
-zoneskip=siint Skip the specified number of bytes when zonesize data has
+zoneskip=int Skip the specified number of bytes when zonesize data has
been read. The two zone options can be used to only do
io on zones of a file.
read_iolog=str Open an iolog with the specified file name and replay the
io patterns it contains. This can be used to store a
- workload and replay it sometime later.
-
-write_bw_log If given, write a bandwidth log of the jobs in this job
+ workload and replay it sometime later. The iolog given
+ may also be a blktrace binary file, which allows fio
+ to replay a workload captured by blktrace. See blktrace
+ for how to capture such logging data. For blktrace replay,
+ the file needs to be turned into a blkparse binary data
+ file first (blktrace <device> -d file_for_fio.bin).
+
+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
script uses gnuplot to turn these text files into nice
- graphs.
+ graphs. See write_log_log for behaviour of given
+ filename. For this option, the postfix is _bw.log.
-write_lat_log Same as write_bw_log, except that this option stores io
- completion latencies instead.
+write_lat_log=str Same as write_bw_log, except that this option stores io
+ completion latencies instead. 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. So if one specifies
-lockmem=siint Pin down the specified amount of memory with mlock(2). Can
+ write_lat_log=foo
+
+ The actual log names will be foo_clat.log and foo_slat.log.
+ This helps fio_generate_plot fine the logs automatically.
+
+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.
percentage of CPU cycles.
cpuchunks=int If the job is a CPU cycle eater, split the load into
- cycles of the given time. In milliseconds.
+ cycles of the given time. In microseconds.
+
+disk_util=bool Generate disk utilization statistics, if the platform
+ supports it. Defaults to on.
+
+disable_clat=bool Disable measurements of completion latency numbers. Useful
+ only for cutting back the number of calls to gettimeofday,
+ as that does impact performance at really high IOPS rates.
+ Note that to really get rid of a large amount of these
+ calls, this option must be used with disable_slat and
+ disable_bw as well.
+
+disable_slat=bool Disable measurements of submission latency numbers. See
+ disable_clat.
+
+disable_bw=bool Disable measurements of throughput/bandwidth numbers. See
+ disable_clat.
+
+gtod_reduce=bool Enable all of the gettimeofday() reducing options
+ (disable_clat, disable_slat, disable_bw) plus reduce
+ precision of the timeout somewhat to really shrink
+ the gettimeofday() call count. With this option enabled,
+ we only do about 0.4% of the gtod() calls we would have
+ done if all time keeping was enabled.
+
+gtod_cpu=int Sometimes it's cheaper to dedicate a single thread of
+ execution to just getting the current time. Fio (and
+ databases, for instance) are very intensive on gettimeofday()
+ calls. With this option, you can set one CPU aside for
+ doing nothing but logging current time to a shared memory
+ location. Then the other threads/processes that run IO
+ workloads need only copy that segment, instead of entering
+ the kernel with a gettimeofday() call. The CPU set aside
+ for doing these time calls will be excluded from other
+ uses. Fio will manually clear it from the CPU mask of other
+ jobs.
6.0 Interpreting the output
P Thread setup, but not started.
C Thread created.
I Thread initialized, waiting.
+ p Thread running pre-reading file(s).
R Running, doing sequential reads.
r Running, doing random reads.
W Running, doing sequential writes.
M Running, doing mixed sequential reads/writes.
m Running, doing mixed random reads/writes.
F Running, currently waiting for fsync()
-V Running, doing verification of written data.
+ V Running, doing verification of written data.
E Thread exited, not reaped by main thread yet.
_ Thread reaped.
The other values are fairly self explanatory - number of threads
-currently running and doing io, rate of io since last check, and the estimated
-completion percentage and time for the running group. It's impossible to
-estimate runtime of the following groups (if any).
+currently running and doing io, rate of io since last check (read speed
+listed first, then write speed), and the estimated completion percentage
+and time for the running group. It's impossible to estimate runtime of
+the following groups (if any).
When fio is done (or interrupted by ctrl-c), it will show the data for
each thread, group of threads, and disks in that order. For each data
slat (msec): min= 0, max= 136, avg= 0.03, stdev= 1.92
clat (msec): min= 0, max= 631, avg=48.50, stdev=86.82
bw (KiB/s) : min= 0, max= 1196, per=51.00%, avg=664.02, stdev=681.68
- cpu : usr=1.49%, sys=0.25%, ctx=7969
+ cpu : usr=1.49%, sys=0.25%, ctx=7969, majf=0, minf=17
IO depths : 1=0.1%, 2=0.3%, 4=0.5%, 8=99.0%, 16=0.0%, 32=0.0%, >32=0.0%
+ submit : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
+ complete : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
issued r/w: total=0/32768, short=0/0
lat (msec): 2=1.6%, 4=0.0%, 10=3.2%, 20=12.8%, 50=38.4%, 100=24.8%,
lat (msec): 250=15.2%, 500=0.0%, 750=0.0%, 1000=0.0%, >=2048=0.0%
slat= Submission latency (avg being the average, stdev being the
standard deviation). This is the time it took to submit
the io. For sync io, the slat is really the completion
- latency, since queue/complete is one operation there.
+ latency, since queue/complete is one operation there. This
+ value can be in milliseconds or microseconds, fio will choose
+ the most appropriate base and print that. In the example
+ above, milliseconds is the best scale.
clat= Completion latency. Same names as slat, this denotes the
time from submission to completion of the io pieces. For
sync io, clat will usually be equal (or very close) to 0,
only really useful if the threads in this group are on the
same disk, since they are then competing for disk access.
cpu= CPU usage. User and system time, along with the number
- of context switches this thread went through.
+ of context switches this thread went through, usage of
+ system and user time, and finally the number of major
+ and minor page faults.
IO depths= The distribution of io depths over the job life time. The
numbers are divided into powers of 2, so for example the
16= entries includes depths up to that value but higher
than the previous entry. In other words, it covers the
range from 16 to 31.
+IO submit= How many pieces of IO were submitting in a single submit
+ call. Each entry denotes that amount and below, until
+ the previous entry - eg, 8=100% mean that we submitted
+ anywhere in between 5-8 ios per submit call.
+IO complete= Like the above submit number, but for completions instead.
IO issued= The number of read/write requests issued, and how many
of them were short.
IO latencies= The distribution of IO completion latencies. This is the
client1;0;0;1906777;1090804;1790;0;0;0.000000;0.000000;0;0;0.000000;0.000000;929380;1152890;25.510151%;1078276.333333;128948.113404;0;0;0;0;0;0.000000;0.000000;0;0;0.000000;0.000000;0;0;0.000000%;0.000000;0.000000;100.000000%;0.000000%;324;100.0%;0.0%;0.0%;0.0%;0.0%;0.0%;0.0%;100.0%;0.0%;0.0%;0.0%;0.0%;0.0%
;0.0%;0.0%;0.0%;0.0%;0.0%
+To enable terse output, use the --minimal command line option.
+
Split up, the format is as follows:
jobname, groupid, error
Submission latency: min, max, mean, deviation
Completion latency: min, max, mean, deviation
Bw: min, max, aggregate percentage of total, mean, deviation
- CPU usage: user, system, context switches
+ CPU usage: user, system, context switches, major faults, minor faults
IO depths: <=1, 2, 4, 8, 16, 32, >=64
IO latencies: <=2, 4, 10, 20, 50, 100, 250, 500, 750, 1000, >=2000
Text description
projects / fio.git / blobdiff