X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;ds=sidebyside;f=HOWTO;h=1c89d75f29cf6a01264d9f6dbbaaefc9b529a9e8;hb=9195552e8fca86b682a86fc7ab0fb6eacb433f16;hp=e69cf4130696c55bf0af6cc3f224d6136af5666b;hpb=49ccb8c10036ca0dca1238558c390f61f769c3c9;p=fio.git diff --git a/HOWTO b/HOWTO index e69cf413..1c89d75f 100644 --- a/HOWTO +++ b/HOWTO @@ -223,7 +223,8 @@ a string. The following types are used: 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 @@ -261,7 +262,8 @@ description=str Text description of the job. Doesn't do anything except 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 @@ -428,11 +430,25 @@ size=int The total size of file io for this job. Fio will run until 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 @@ -517,6 +533,8 @@ bs_is_seq_rand If this option is set, fio will use the normal read,write 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 @@ -927,6 +945,18 @@ cpus_allowed=str Controls the same options as cpumask, but it allows a text 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, @@ -1068,6 +1098,13 @@ 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. +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. @@ -1098,6 +1135,10 @@ verify=str If writing to a file, fio can verify the file contents 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. @@ -1106,7 +1147,9 @@ verify=str If writing to a file, fio can verify the file contents 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 @@ -1470,6 +1513,8 @@ that defines them is selected. [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 @@ -1555,6 +1600,7 @@ I Thread initialized, waiting or generating necessary data. 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