one by appending a ':<nr>' to the end of the string given.
For a random read, it would look like 'rw=randread:8' for
passing in an offset modifier with a value of 8. If the
- postfix is used with a sequential IO pattern, then the value
+ suffix is used with a sequential IO pattern, then the value
specified will be added to the generated offset for each IO.
For instance, using rw=write:4k will skip 4k for every
write. It turns sequential IO into sequential IO with holes.
channel semantics (Send/Recv) for the
InfiniBand, RoCE and iWARP protocols.
+ 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_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
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.
+create_only=bool If true, fio will only run the setup phase of the job.
+ If files need to be laid out or updated on disk, only
+ that will be done. The actual job contents are not
+ executed.
+
pre_read=bool If this is given, files will be pre-read into memory before
starting the given IO operation. This will also clear
the 'invalidate' flag, since it is pointless to pre-read
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
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 write_log_log for behaviour of given
- filename. For this option, the postfix is _bw.log.
+ graphs. See write_lat_log for behaviour of given
+ filename. For this option, the suffix is _bw.log.
write_lat_log=str Same as write_bw_log, except that this option stores io
submission, completion, and total latencies instead. If no
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
[net] listen For TCP network connections, tell fio to listen for incoming
connections rather than initiating an outgoing connection. The
hostname must be omitted if this option is used.
+[e4defrag] donorname=str
+ File will be used as a block donor(swap extents between files)
+[e4defrag] inplace=int
+ Configure donor file blocks allocation strategy
+ 0(default): Preallocate donor's file on init
+ 1 : allocate space immidietly inside defragment event,
+ and free right after event
+
6.0 Interpreting the output
E Thread exited, not reaped by main thread yet.
_ Thread reaped, or
X Thread reaped, exited with an error.
+K Thread reaped, exited due to signal.
The other values are fairly self explanatory - number of threads
currently running and doing io, rate of io since last check (read speed
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.
+ above, milliseconds is the best scale. Note: in --minimal mode
+ latencies are always expressed in microseconds.
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,
util= The disk utilization. A value of 100% means we kept the disk
busy constantly, 50% would be a disk idling half of the time.
+It is also possible to get fio to dump the current output while it is
+running, without terminating the job. To do that, send fio the USR1 signal.
+
7.0 Terse output
----------------
terse version, fio version, jobname, groupid, error
READ status:
Total IO (KB), bandwidth (KB/sec), IOPS, runtime (msec)
- Submission latency: min, max, mean, deviation
- Completion latency: min, max, mean, deviation
+ Submission latency: min, max, mean, deviation (usec)
+ Completion latency: min, max, mean, deviation (usec)
Completion latency percentiles: 20 fields (see below)
- Total latency: min, max, mean, deviation
- Bw: min, max, aggregate percentage of total, mean, deviation
+ Total latency: min, max, mean, deviation (usec)
+ Bw (KB/s): min, max, aggregate percentage of total, mean, deviation
WRITE status:
Total IO (KB), bandwidth (KB/sec), IOPS, runtime (msec)
- Submission latency: min, max, mean, deviation
- Completion latency: min, max, mean, deviation
+ Submission latency: min, max, mean, deviation (usec)
+ Completion latency: min, max, mean, deviation (usec)
Completion latency percentiles: 20 fields (see below)
- Total latency: min, max, mean, deviation
- Bw: min, max, aggregate percentage of total, mean, deviation
+ Total latency: min, max, mean, deviation (usec)
+ Bw (KB/s): min, max, aggregate percentage of total, mean, deviation
CPU usage: user, system, context switches, major faults, minor faults
IO depths: <=1, 2, 4, 8, 16, 32, >=64
IO latencies microseconds: <=2, 4, 10, 20, 50, 100, 250, 500, 750, 1000
projects / fio.git / blobdiff