one wants to simulate.
.SH OPTIONS
.TP
+.BI \-\-debug \fR=\fPtype
+Enable verbose tracing of various fio actions. May be `all' for all types
+or individual types separated by a comma (eg \-\-debug=io,file). `help' will
+list all available tracing options.
+.TP
.BI \-\-output \fR=\fPfilename
Write output to \fIfilename\fR.
.TP
.B \-\-minimal
Print statistics in a terse, semicolon-delimited format.
.TP
+.B \-\-version
+Display version information and exit.
+.TP
+.BI \-\-terse\-version \fR=\fPversion
+Set terse version output format (Current version 3, or older version 2).
+.TP
+.B \-\-help
+Display usage information and exit.
+.TP
+.BI \-\-cmdhelp \fR=\fPcommand
+Print help information for \fIcommand\fR. May be `all' for all commands.
+.TP
.BI \-\-showcmd \fR=\fPjobfile
Convert \fIjobfile\fR to a set of command-line options.
.TP
Specifies when real-time ETA estimate should be printed. \fIwhen\fR may
be one of `always', `never' or `auto'.
.TP
+.BI \-\-readonly
+Turn on safety read-only checks, preventing any attempted write.
+.TP
.BI \-\-section \fR=\fPsec
-Only run section \fIsec\fR from job file.
+Only run section \fIsec\fR from job file. Multiple of these options can be given, adding more sections to run.
.TP
-.BI \-\-cmdhelp \fR=\fPcommand
-Print help information for \fIcommand\fR. May be `all' for all commands.
+.BI \-\-alloc\-size \fR=\fPkb
+Set the internal smalloc pool size to \fIkb\fP kilobytes.
.TP
-.BI \-\-debug \fR=\fPtype
-Enable verbose tracing of various fio actions. May be `all' for all types
-or individual types seperated by a comma (eg \-\-debug=io,file). `help' will
-list all available tracing options.
+.BI \-\-warnings\-fatal
+All fio parser warnings are fatal, causing fio to exit with an error.
.TP
-.B \-\-help
-Display usage information and exit.
+.BI \-\-max\-jobs \fR=\fPnr
+Set the maximum allowed number of jobs (threads/processes) to suport.
.TP
-.B \-\-version
-Display version information and exit.
+.BI \-\-server \fR=\fPargs
+Start a backend server, with \fIargs\fP specifying what to listen to. See client/server section.
+.TP
+.BI \-\-daemonize \fR=\fPpidfile
+Background a fio server, writing the pid to the given pid file.
+.TP
+.BI \-\-client \fR=\fPhost
+Instead of running the jobs locally, send and run them on the given host.
.SH "JOB FILE FORMAT"
Job files are in `ini' format. They consist of one or more
job definitions, which begin with a job name in square brackets and
of the value. Accepted suffixes are `k', 'M', 'G', 'T', and 'P', denoting
kilo (1024), mega (1024^2), giga (1024^3), tera (1024^4), and peta (1024^5)
respectively. The suffix is not case sensitive. If prefixed with '0x', the
-value is assumed to be base 16 (hexadecimal). A suffix may include a trailing
-'b', for instance 'kb' is identical to 'k'. You can specify a base 10 value
+value is assumed to be base 16 (hexadecimal). A suffix may include a trailing 'b',
+for instance 'kb' is identical to 'k'. You can specify a base 10 value
by using 'KiB', 'MiB', 'GiB', etc. This is useful for disk drives where
values are often given in base 10 values. Specifying '30GiB' will get you
30*1000^3 bytes.
\fIupper\fR may contain a suffix as described above. If an option allows two
sets of ranges, they are separated with a `,' or `/' character. For example:
`8\-8k/8M\-4G'.
+.TP
+.I float_list
+List of floating numbers: A list of floating numbers, separated by
+a ':' charcater.
.SS "Parameter List"
.TP
.BI name \fR=\fPstr
specify a number of IO's to do before getting a new offset, this is one by
appending a `:\fI<nr>\fR to the end of the string given. For a random read, it
would look like \fBrw=randread:8\fR for passing in an offset modifier with a
-value of 8. See the \fBrw_sequencer\fR option.
+value of 8. If the postfix is used with a sequential IO pattern, then the value
+specified will be added to the generated offset for each IO. For instance,
+using \fBrw=write:4k\fR will skip 4k for every write. It turns sequential IO
+into sequential IO with holes. See the \fBrw_sequencer\fR option.
.RE
.TP
.BI rw_sequencer \fR=\fPstr
Seed the random number generator in a predictable way so results are repeatable
across runs. Default: true.
.TP
-.BI fallocate \fR=\fPbool
-By default, fio will use fallocate() to advise the system of the size of the
-file we are going to write. This can be turned off with fallocate=0. May not
-be available on all supported platforms.
+.BI use_os_rand \fR=\fPbool
+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 internal generator, which is often of better quality and
+faster. Default: false.
+.TP
+.BI fallocate \fR=\fPstr
+Whether pre-allocation is performed when laying down files. Accepted values
+are:
+.RS
+.RS
+.TP
+.B none
+Do not pre-allocate space.
+.TP
+.B posix
+Pre-allocate via posix_fallocate().
+.TP
+.B keep
+Pre-allocate via fallocate() with FALLOC_FL_KEEP_SIZE set.
+.TP
+.B 0
+Backward-compatible alias for 'none'.
+.TP
+.B 1
+Backward-compatible alias for 'posix'.
+.RE
+.P
+May not be available on all supported platforms. 'keep' is only
+available on Linux. If using ZFS on Solaris this must be set to 'none'
+because ZFS doesn't support it. Default: 'posix'.
+.RE
.TP
.BI fadvise_hint \fR=\fPbool
Disable use of \fIposix_fadvise\fR\|(2) to advise the kernel what I/O patterns
Unless \fBnrfiles\fR and \fBfilesize\fR options are given, this amount will be
divided between the available files for 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.
+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.
.TP
-.BI fill_device \fR=\fPbool
+.BI fill_device \fR=\fPbool "\fR,\fB fill_fs" \fR=\fPbool
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.
For a read workload, the mount point will be filled first then IO started on
-the result.
+the result. This option doesn't make sense if operating on a raw device node,
+since the size of that is already known by the file system. Additionally,
+writing beyond end-of-device will not return ENOSPC there.
.TP
.BI filesize \fR=\fPirange
Individual file sizes. May be a range, in which case \fBfio\fR will select sizes
not just even splits between them. With this option, you can weight various
block sizes for exact control of the issued IO for a job that has mixed
block sizes. The format of the option is bssplit=blocksize/percentage,
-optionally adding as many definitions as needed seperated by a colon.
+optionally adding as many definitions as needed separated by a colon.
Example: bssplit=4k/10:64k/50:32k/40 would issue 50% 64k blocks, 10% 4k
blocks and 40% 32k blocks. \fBbssplit\fR also supports giving separate
splits to reads and writes. The format is identical to what the
if zero_buffers isn't specified, naturally. If data verification is enabled,
refill_buffers is also automatically enabled.
.TP
+.BI scramble_buffers \fR=\fPbool
+If \fBrefill_buffers\fR is too costly and the target is using data
+deduplication, then setting this option will slightly modify the IO buffer
+contents to defeat normal de-dupe attempts. This is not enough to defeat
+more clever block compression attempts, but it will stop naive dedupe
+of blocks. Default: true.
+.TP
.BI nrfiles \fR=\fPint
Number of files to use for this job. Default: 1.
.TP
coalescing adjacents IOs into a single submission.
.TP
.B libaio
-Linux native asynchronous I/O.
+Linux native asynchronous I/O. This engine also has a sub-option,
+\fBuserspace_reap\fR. To set it, use \fBioengine=libaio:userspace_reap\fR.
+Normally, with the libaio engine in use, fio will use the
+\fIio_getevents\fR\|(3) system call to reap newly returned events. With this
+flag turned on, the AIO ring will be read directly from user-space to reap
+events. The reaping mode is only enabled when polling for a minimum of \fB0\fR
+events (eg when \fBiodepth_batch_complete=0\fR).
.TP
.B posixaio
POSIX asynchronous I/O using \fIaio_read\fR\|(3) and \fIaio_write\fR\|(3).
.TP
.B net
Transfer over the network. \fBfilename\fR must be set appropriately to
-`\fIhost\fR/\fIport\fR' regardless of data direction. If receiving, only the
-\fIport\fR argument is used.
+`\fIhost\fR,\fIport\fR,\fItype\fR' regardless of data direction. \fItype\fR
+is one of \fBtcp\fR, \fBudp\fR, or \fBunix\fR. For UNIX domain sockets,
+the \fIhost\fR parameter is a file system path.
.TP
.B netsplice
Like \fBnet\fR, but uses \fIsplice\fR\|(2) and \fIvmsplice\fR\|(2) to map data
.br
See <http://www.xmailserver.org/guasi\-lib.html>.
.TP
+.B rdma
+The RDMA I/O engine supports both RDMA memory semantics (RDMA_WRITE/RDMA_READ)
+and channel semantics (Send/Recv) for the InfiniBand, RoCE and iWARP protocols.
+.TP
.B external
Loads an external I/O engine object file. Append the engine filename as
`:\fIenginepath\fR'.
this parameter is given, a new offset will be chosen without looking at past
I/O history. This parameter is mutually exclusive with \fBverify\fR.
.TP
-.B softrandommap
+.BI softrandommap \fR=\fPbool
See \fBnorandommap\fR. 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
use.
.RE
.TP
-.BI iomem_align \fR=\fPint
+.BI iomem_align \fR=\fPint "\fR,\fP mem_align" \fR=\fPint
This indiciates the memory alignment of the IO memory buffers. Note that the
given alignment is applied to the first IO unit buffer, if using \fBiodepth\fR
the alignment of the following buffers are given by the \fBbs\fR used. In
Average bandwidth calculations over the given time in milliseconds. Default:
500ms.
.TP
+.BI iopsavgtime \fR=\fPint
+Average IOPS calculations over the given time in milliseconds. Default:
+500ms.
+.TP
.BI create_serialize \fR=\fPbool
If true, serialize file creation for the jobs. Default: true.
.TP
\fBverify_backlog_batch\fR is larger than \fBverify_backlog\fR, some blocks
will be verified more than once.
.TP
-.B stonewall
-Wait for preceeding jobs in the job file to exit before starting this one.
+.B stonewall "\fR,\fP wait_for_previous"
+Wait for preceding jobs in the job file to exit before starting this one.
\fBstonewall\fR implies \fBnew_group\fR.
.TP
.B new_group
from. Setting \fBreplay_redirect\fR causes all IOPS to be replayed onto the
single specified device regardless of the device it was recorded from.
.TP
-.B write_bw_log \fR=\fPstr
+.BI write_bw_log \fR=\fPstr
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. See \fBwrite_log_log\fR for behaviour of given filename. For this
option, the postfix is _bw.log.
.TP
-.B write_lat_log \fR=\fPstr
+.BI write_lat_log \fR=\fPstr
Same as \fBwrite_bw_log\fR, but writes I/O completion latencies. 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.
.TP
-.B disable_lat \fR=\fPbool
+.BI write_iops_log \fR=\fPstr
+Same as \fBwrite_bw_log\fR, 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.
+.TP
+.BI disable_lat \fR=\fPbool
Disable measurements of total 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.
.TP
-.B disable_clat \fR=\fPbool
-Disable measurements of submission latency numbers. See \fBdisable_lat\fR.
+.BI disable_clat \fR=\fPbool
+Disable measurements of completion latency numbers. See \fBdisable_lat\fR.
.TP
-.B disable_slat \fR=\fPbool
+.BI disable_slat \fR=\fPbool
Disable measurements of submission latency numbers. See \fBdisable_lat\fR.
.TP
-.B disable_bw_measurement \fR=\fPbool
+.BI disable_bw_measurement \fR=\fPbool
Disable measurements of throughput/bandwidth numbers. See \fBdisable_lat\fR.
.TP
.BI lockmem \fR=\fPint
The system must have a mounted cgroup blkio mount point for this to work. If
your system doesn't have it mounted, you can do so with:
-# mount -t cgroup -o blkio none /cgroup
+# mount \-t cgroup \-o blkio none /cgroup
.TP
.BI cgroup_weight \fR=\fPint
Set the weight of the cgroup to this value. See the documentation that comes
.TP
.BI gid \fR=\fPint
Set group ID, see \fBuid\fR.
+.TP
+.BI clat_percentiles \fR=\fPbool
+Enable the reporting of percentiles of completion latencies.
+.TP
+.BI percentile_list \fR=\fPfloat_list
+Overwrite the default list of percentiles for completion
+latencies. Each number is a floating number in the range (0,100], and
+the maximum length of the list is 20. Use ':' to separate the
+numbers. For example, \-\-percentile_list=99.5:99.9 will cause fio to
+report the values of completion latency below which 99.5% and 99.9% of
+the observed latencies fell, respectively.
.SH OUTPUT
While running, \fBfio\fR will display the status of the created jobs. For
example:
change. The fields are:
.P
.RS
-.B version, jobname, groupid, error
+.B terse version, fio version, jobname, groupid, error
.P
Read status:
.RS
-.B KB I/O, bandwidth \fR(KB/s)\fP, runtime \fR(ms)\fP
+.B Total I/O \fR(KB)\fP, bandwidth \fR(KB/s)\fP, IOPS, runtime \fR(ms)\fP
.P
Submission latency:
.RS
.RS
.B min, max, mean, standard deviation
.RE
+Completion latency percentiles (20 fields):
+.RS
+.B Xth percentile=usec
+.RE
Total latency:
.RS
.B min, max, mean, standard deviation
.P
Write status:
.RS
-.B KB I/O, bandwidth \fR(KB/s)\fP, runtime \fR(ms)\fP
+.B Total I/O \fR(KB)\fP, bandwidth \fR(KB/s)\fP, IOPS, runtime \fR(ms)\fP
.P
Submission latency:
.RS
.RS
.B min, max, mean, standard deviation
.RE
+Completion latency percentiles (20 fields):
+.RS
+.B Xth percentile=usec
+.RE
Total latency:
.RS
.B min, max, mean, standard deviation
.RE
.RE
.P
-Error Info (dependant on continue_on_error, default off):
+Disk utilization (1 for each disk used):
+.RS
+.B name, read ios, write ios, read merges, write merges, read ticks, write ticks, read in-queue time, write in-queue time, disk utilization percentage
+.RE
+.P
+Error Info (dependent on continue_on_error, default off):
.RS
.B total # errors, first error code
.RE
.P
.B text description (if provided in config - appears on newline)
.RE
+.SH CLIENT / SERVER
+Normally you would run fio as a stand-alone application on the machine
+where the IO workload should be generated. However, it is also possible to
+run the frontend and backend of fio separately. This makes it possible to
+have a fio server running on the machine(s) where the IO workload should
+be running, while controlling it from another machine.
+
+To start the server, you would do:
+
+\fBfio \-\-server=args\fR
+
+on that machine, 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 v4, 'ip6' for TCP/IP v6, or 'sock' for a local unix domain socket.
+'hostname' is either a hostname or IP address, and 'port' is the port to
+listen to (only valid for TCP/IP, not a local socket). Some examples:
+
+1) fio --server
+
+ Start a fio server, listening on all interfaces on the default port (8765).
+
+2) fio --server=ip:hostname,4444
+
+ Start a fio server, listening on IP belonging to hostname and on port 4444.
+
+3) fio --server=ip6:::1,4444
+
+ Start a fio server, listening on IPv6 localhost ::1 and on port 4444.
+
+4) fio --server=,4444
+
+ Start a fio server, listening on all interfaces on port 4444.
+
+5) fio --server=1.2.3.4
+
+ Start a fio server, listening on IP 1.2.3.4 on the default port.
+
+6) fio --server=sock:/tmp/fio.sock
+
+ Start a fio server, listening on the local socket /tmp/fio.sock.
+
+When a server is running, you can connect to it from a client. The client
+is run with:
+
+fio --local-args --client=server --remote-args <job file(s)>
+
+where --local-args are arguments that are local to the client where it is
+running, 'server' is the connect string, and --remote-args and <job file(s)>
+are sent to the server. The 'server' string follows the same format as it
+does on the server side, to allow IP/hostname/socket and port strings.
+You can connect to multiple clients as well, to do that you could run:
+
+fio --client=server2 --client=server2 <job file(s)>
.SH AUTHORS
+
.B fio
was written by Jens Axboe <jens.axboe@oracle.com>,
now Jens Axboe <jaxboe@fusionio.com>.
projects / fio.git / blobdiff