X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=HOWTO;h=6391b82a9c79b31fe3e3b0f2fac2dd0b6caf57ae;hp=2f70b94fe0637369ad860dfdb6ee6de7095bd4eb;hb=2ab9e98b300c35d3b7807f74d404ce3c5de33fb3;hpb=d54fce84e5a022d2c4790fb5c13235d3368f4f08 diff --git a/HOWTO b/HOWTO index 2f70b94f..6391b82a 100644 --- a/HOWTO +++ b/HOWTO @@ -605,13 +605,13 @@ ioengine=str Defines how the job issues io to the file. The following 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_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 - + external Prefix to specify loading an external IO engine object file. Append the engine filename, eg ioengine=external:/tmp/foo.o @@ -716,6 +716,25 @@ rwmixwrite=int How large a percentage of the mix should be writes. If both if fio is asked to limit reads or writes to a certain rate. If that is the case, then the distribution may be skewed. +random_distribution=str:float By default, fio will use a completely uniform + random distribution when asked to perform random IO. Sometimes + it is useful to skew the distribution in specific ways, + ensuring that some parts of the data is more hot than others. + fio includes the following distribution models: + + random Uniform random distribution + zipf Zipf distribution + pareto Pareto distribution + + When using a zipf or pareto distribution, an input value + is also needed to define the access pattern. For zipf, this + is the zipf theta. For pareto, it's the pareto power. Fio + includes a test program, genzipf, that can be used visualize + what the given input values will yield in terms of hit rates. + If you wanted to use zipf with a theta of 1.2, you would use + random_distribution=zipf:1.2 as the option. If a non-uniform + model is used, fio will disable use of the random map. + norandommap Normally fio will cover every block of the file when doing random IO. If this option is given, fio will just get a new random offset without looking at past io history. This @@ -780,6 +799,9 @@ rate_iops_min=int If fio doesn't meet this rate of IO, it will cause the job to exit. The same format as rate is used for read vs write seperation. +max_latency=int If set, fio will exit the job if it exceeds this maximum + latency. It will exit with an ETIME error. + ratecycle=int Average bandwidth for 'rate' and 'ratemin' over this number of milliseconds. @@ -799,6 +821,24 @@ 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. +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, + export the following environment variables, + export EXTFLAGS+=" -DFIO_HAVE_LIBNUMA " + export EXTLIBS+=" -lnuma " + +numa_mem_policy=str Set this job's memory policy and corresponding NUMA + nodes. Format of the argements: + [:] + `mode' is one of the following memory policy: + default, prefer, bind, interleave, local + For `default' and `local' memory policy, no node is + needed to be specified. + For `prefer', only one node is allowed. + For `bind' and `interleave', it allow comma delimited + list of numbers, A-B ranges, or 'all'. + 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 @@ -1053,22 +1093,22 @@ wait_for_previous Wait for preceeding jobs in the job file to exit, before points in the job file. A stone wall also implies starting a new reporting group. -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 separated by a stone wall (or if it's a group - by itself, with the numjobs option). +new_group Start a new reporting group. See: group_reporting. numjobs=int Create the specified number of clones of this job. May be used to setup a larger number of threads/processes doing - the same thing. We regard that grouping of jobs as a - specific group. - -group_reporting If 'numjobs' is set, it may be interesting to display - statistics for the group as a whole instead of for each - individual job. This is especially true of 'numjobs' is - large, looking at individual thread/process output quickly - becomes unwieldy. If 'group_reporting' is specified, fio - will show the final report per-group instead of per-job. + the same thing. Each thread is reported separately; to see + statistics for all clones as a whole, use group_reporting in + conjunction with new_group. + +group_reporting It may sometimes be interesting to display statistics for + groups of jobs as a whole instead of for each individual job. + This is especially true if 'numjobs' is used; looking at + individual thread/process output quickly becomes unwieldy. + To see the final report per-group instead of per-job, use + 'group_reporting'. Jobs in a file will be part of the same + reporting group, unless if separated by a stonewall, or by + using 'new_group'. thread fio defaults to forking jobs, however if this option is given, fio will use pthread_create(3) to create threads @@ -1248,6 +1288,19 @@ continue_on_error=str Normally fio will exit the job on the first observed 1 Backward-compatible alias for 'all'. +ignore_error=str Sometimes you want to ignore some errors during test + in that case you can specify error list for each error type. + ignore_error=READ_ERR_LIST,WRITE_ERR_LIST,VERIFY_ERR_LIST + errors for given error type is separated with ':'. Error + may be symbol ('ENOSPC', 'ENOMEM') or integer. + Example: + ignore_error=EAGAIN,ENOSPC:122 + This option will ignore EAGAIN from READ, and ENOSPC and + 122(EDQUOT) from WRITE. + +error_dump=bool If set dump every error even if it is non fatal, true + by default. If disabled only fatal error will be dumped + cgroup=str Add job to this control group. If it doesn't exist, it will be created. The system must have a mounted cgroup blkio mount point for this to work. If your system doesn't have it @@ -1315,7 +1368,7 @@ that defines them is selected. [net] proto=str The network protocol to use. Accepted values are: tcp Transmission control protocol - udp Unreliable datagram protocol + udp User datagram protocol unix UNIX domain socket When the protocol is TCP or UDP, the port must also be given, @@ -1351,7 +1404,7 @@ Idle Run ---- --- P Thread setup, but not started. C Thread created. -I Thread initialized, waiting. +I Thread initialized, waiting or generating necessary data. p Thread running pre-reading file(s). R Running, doing sequential reads. r Running, doing random reads.