fio --- fio is a tool that will spawn a number of threads or processes doing a particular type of io action as specified by the user. fio takes a number of global parameters, each inherited by the thread unless otherwise parameters given to them overriding that setting is given. The typical use of fio is to write a job file matching the io load one wants to simulate. Source ------ fio resides in a git repo, the canonical place is: git://git.kernel.dk/fio.git When inside a corporate firewall, git:// URL sometimes does not work. If git:// does not work, use the http protocol instead: http://git.kernel.dk/fio.git Snapshots are frequently generated and include the git meta data as well. Snapshots can download from: http://brick.kernel.dk/snaps/ There are also two official mirrors. Both of these are automatically synced with the main repository, when changes are pushed. If the main repo is down for some reason, either one of these is safe to use as a backup: git://git.kernel.org/pub/scm/linux/kernel/git/axboe/fio.git https://git.kernel.org/pub/scm/linux/kernel/git/axboe/fio.git or git://github.com/axboe/fio.git https://github.com/axboe/fio.git Binary packages --------------- Debian: Starting with Debian "Squeeze", fio packages are part of the official Debian repository. http://packages.debian.org/search?keywords=fio Ubuntu: Starting with Ubuntu 10.04 LTS (aka "Lucid Lynx"), fio packages are part of the Ubuntu "universe" repository. http://packages.ubuntu.com/search?keywords=fio Red Hat, CentOS & Co: Dag Wieërs has RPMs for Red Hat related distros, find them here: http://dag.wieers.com/rpm/packages/fio/ Mandriva: Mandriva has integrated fio into their package repository, so installing on that distro should be as easy as typing 'urpmi fio'. Solaris: Packages for Solaris are available from OpenCSW. Install their pkgutil tool (http://www.opencsw.org/get-it/pkgutil/) and then install fio via 'pkgutil -i fio'. Windows: Bruce Cran <bruce@cran.org.uk> has fio packages for Windows at http://www.bluestop.org/fio/ . Mailing list ------------ The fio project mailing list is meant for anything related to fio including general discussion, bug reporting, questions, and development. An automated mail detailing recent commits is automatically sent to the list at most daily. The list address is fio@vger.kernel.org, subscribe by sending an email to majordomo@vger.kernel.org with subscribe fio in the body of the email. Archives can be found here: http://www.spinics.net/lists/fio/ and archives for the old list can be found here: http://maillist.kernel.dk/fio-devel/ Building -------- Just type 'configure', 'make' and 'make install'. Note that GNU make is required. On BSD it's available from devel/gmake; on Solaris it's in the SUNWgmake package. On platforms where GNU make isn't the default, type 'gmake' instead of 'make'. Configure will print the enabled options. Note that on Linux based platforms, the libaio development packages must be installed to use the libaio engine. Depending on distro, it is usually called libaio-devel or libaio-dev. For gfio, gtk 2.18 (or newer), associated glib threads, and cairo are required to be installed. gfio isn't built automatically and can be enabled with a --enable-gfio option to configure. To build FIO with a cross-compiler: $ make clean $ make CROSS_COMPILE=/path/to/toolchain/prefix Configure will attempt to determine the target platform automatically. It's possible to build fio for ESX as well, use the --esx switch to configure. Windows ------- On Windows, Cygwin (http://www.cygwin.com/) is required in order to build fio. To create an MSI installer package install WiX 3.8 from http://wixtoolset.org and run dobuild.cmd from the os/windows directory. How to compile fio on 64-bit Windows: 1. Install Cygwin (http://www.cygwin.com/). Install 'make' and all packages starting with 'mingw64-i686' and 'mingw64-x86_64'. 2. Open the Cygwin Terminal. 3. Go to the fio directory (source files). 4. Run 'make clean && make -j'. To build fio on 32-bit Windows, run './configure --build-32bit-win' before 'make'. It's recommended that once built or installed, fio be run in a Command Prompt or other 'native' console such as console2, since there are known to be display and signal issues when running it under a Cygwin shell (see http://code.google.com/p/mintty/issues/detail?id=56 for details). Command line ------------ $ fio --debug Enable some debugging options (see below) --parse-only Parse options only, don't start any IO --output Write output to file --runtime Runtime in seconds --bandwidth-log Generate per-job bandwidth logs --minimal Minimal (terse) output --output-format=type Output format (terse,json,json+,normal) --terse-version=type Terse version output format (default 3, or 2 or 4). --version Print version info and exit --help Print this page --cpuclock-test Perform test/validation of CPU clock --crctest[=test] Test speed of checksum functions --cmdhelp=cmd Print command help, "all" for all of them --enghelp=engine Print ioengine help, or list available ioengines --enghelp=engine,cmd Print help for an ioengine cmd --showcmd Turn a job file into command line options --readonly Turn on safety read-only checks, preventing writes --eta=when When ETA estimate should be printed May be "always", "never" or "auto" --eta-newline=time Force a new line for every 'time' period passed --status-interval=t Force full status dump every 't' period passed --section=name Only run specified section in job file. Multiple sections can be specified. --alloc-size=kb Set smalloc pool to this size in kb (def 1024) --warnings-fatal Fio parser warnings are fatal --max-jobs Maximum number of threads/processes to support --server=args Start backend server. See Client/Server section. --client=host Connect to specified backend(s). --remote-config=file Tell fio server to load this local file --idle-prof=option Report cpu idleness on a system or percpu basis (option=system,percpu) or run unit work calibration only (option=calibrate). --inflate-log=log Inflate and output compressed log --trigger-file=file Execute trigger cmd when file exists --trigger-timeout=t Execute trigger af this time --trigger=cmd Set this command as local trigger --trigger-remote=cmd Set this command as remote trigger --aux-path=path 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 file will be regarded as a separate group. fio will stonewall execution between each group. The --readonly option is an extra safety guard to prevent users from accidentally starting a write workload when that is not desired. Fio will only write if rw=write/randwrite/rw/randrw is given. This extra safety net can be used as an extra precaution as --readonly will also enable a write check in the io engine core to prevent writes due to unknown user space bug(s). The --debug option triggers additional logging by fio. Currently, additional logging is available for: process Dump info related to processes file Dump info related to file actions io Dump info related to IO queuing mem Dump info related to memory allocations blktrace Dump info related to blktrace setup verify Dump info related to IO verification all Enable all debug options random Dump info related to random offset generation parse Dump info related to option matching and parsing diskutil Dump info related to disk utilization updates job:x Dump info only related to job number x mutex Dump info only related to mutex up/down ops profile Dump info related to profile extensions time Dump info related to internal time keeping net Dump info related to networking connections rate Dump info related to IO rate switching compress Dump info related to log compress/decompress ? or help Show available debug options. One can specify multiple debug options: e.g. --debug=file,mem will enable file and memory debugging. The --section option allows one to combine related jobs into one file. E.g. one job file could define light, moderate, and heavy sections. Tell fio to run only the "heavy" section by giving --section=heavy command line option. One can also specify the "write" operations in one section and "verify" operation in another section. The --section option only applies to job sections. The reserved 'global' section is always parsed and used. The --alloc-size switch allows one to use a larger pool size for smalloc. If running large jobs with randommap enabled, fio can run out of memory. Smalloc is an internal allocator for shared structures from a fixed size memory pool. The pool size defaults to 1024k and can grow to 128 pools. NOTE: While running .fio_smalloc.* backing store files are visible in /tmp. Job file -------- See the HOWTO file for a complete description of job file syntax and parameters. The --cmdhelp option also lists all options. If used with an option argument, --cmdhelp will detail the given option. The job file format is in the ini style format, as that is easy for the user to review and modify. This README contains the terse version. Job files can describe big and complex setups that are not possible with the command line. Job files are a good practice even for simple jobs since the file provides an easily accessed record of the workload and can include comments. See the examples/ directory for inspiration on how to write job files. Note the copyright and license requirements currently apply to examples/ files. Client/server ------------ Normally fio is invoked as a stand-alone application on the machine where the IO workload should be generated. However, the frontend and backend of fio can be run separately. Ie the fio server can generate an IO workload on the "Device Under Test" while being controlled from another machine. Start the server on the machine which has access to the storage DUT: 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 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. Once a server is running, a "client" can connect to the fio server with: fio --local-args --client=<server> --remote-args <job file(s)> where --local-args are arguments for 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. Fio can connect to multiple servers this way: fio --client=<server1> <job file(s)> --client=<server2> <job file(s)> If the job file is located on the fio server, then you can tell the server to load a local file as well. This is done by using --remote-config: fio --client=server --remote-config /path/to/file.fio Then fio will open this local (to the server) job file instead of being passed one from the client. If you have many servers (example: 100 VMs/containers), you can input a pathname of a file containing host IPs/names as the parameter value for the --client option. For example, here is an example "host.list" file containing 2 hostnames: host1.your.dns.domain host2.your.dns.domain The fio command would then be: fio --client=host.list <job file(s)> In this mode, you cannot input server-specific parameters or job files -- all servers receive the same job file. In order to let fio --client runs use a shared filesystem from multiple hosts, fio --client now prepends the IP address of the server to the filename. For example, if fio is using directory /mnt/nfs/fio and is writing filename fileio.tmp, with a --client hostfile containing two hostnames h1 and h2 with IP addresses 192.168.10.120 and 192.168.10.121, then fio will create two files: /mnt/nfs/fio/192.168.10.120.fileio.tmp /mnt/nfs/fio/192.168.10.121.fileio.tmp Platforms --------- Fio works on (at least) Linux, Solaris, AIX, HP-UX, OSX, NetBSD, OpenBSD, Windows, FreeBSD, and DragonFly. Some features and/or options may only be available on some of the platforms, typically because those features only apply to that platform (like the solarisaio engine, or the splice engine on Linux). Some features are not available on FreeBSD/Solaris even if they could be implemented, I'd be happy to take patches for that. An example of that is disk utility statistics and (I think) huge page support, support for that does exist in FreeBSD/Solaris. Fio uses pthread mutexes for signalling and locking and FreeBSD does not support process shared pthread mutexes. As a result, only threads are supported on FreeBSD. This could be fixed with sysv ipc locking or other locking alternatives. Other *BSD platforms are untested, but fio should work there almost out of the box. Since I don't do test runs or even compiles on those platforms, your mileage may vary. Sending me patches for other platforms is greatly appreciated. There's a lot of value in having the same test/benchmark tool available on all platforms. Note that POSIX aio is not enabled by default on AIX. Messages like these: Symbol resolution failed for /usr/lib/libc.a(posix_aio.o) because: Symbol _posix_kaio_rdwr (number 2) is not exported from dependent module /unix. indicate one needs to enable POSIX aio. Run the following commands as root: # lsdev -C -l posix_aio0 posix_aio0 Defined Posix Asynchronous I/O # cfgmgr -l posix_aio0 # lsdev -C -l posix_aio0 posix_aio0 Available Posix Asynchronous I/O POSIX aio should work now. To make the change permanent: # chdev -l posix_aio0 -P -a autoconfig='available' posix_aio0 changed Author ------ Fio was written by Jens Axboe <axboe@kernel.dk> to enable flexible testing of the Linux IO subsystem and schedulers. He got tired of writing specific test applications to simulate a given workload, and found that the existing io benchmark/test tools out there weren't flexible enough to do what he wanted. Jens Axboe <axboe@kernel.dk> 20060905