defined by \fIioengine\fR. If no \fIioengine\fR is given, list all
available ioengines.
.TP
-.BI \-\-showcmd \fR=\fPjobfile
-Convert \fIjobfile\fR to a set of command\-line options.
+.BI \-\-showcmd
+Convert given \fIjobfile\fRs to a set of command\-line options.
.TP
.BI \-\-readonly
Turn on safety read\-only checks, preventing writes and trims. The \fB\-\-readonly\fR
.RS
.P
.PD 0
-z means Zone
+z means Zone
.P
.PD
.RE
.TP
.B trimwrite
Sequential trim+write sequences. Blocks will be trimmed first,
-then the same blocks will be written to.
+then the same blocks will be written to. So if `io_size=64K' is specified,
+Fio will trim a total of 64K bytes and also write 64K bytes on the same
+trimmed blocks. This behaviour will be consistent with `number_ios' or
+other Fio options limiting the total bytes or number of I/O's.
.RE
.P
Fio defaults to read if the option is not specified. For the mixed I/O
effectively caps the file size at `real_size \- offset'. Can be combined with
\fBsize\fR to constrain the start and end range of the I/O workload.
A percentage can be specified by a number between 1 and 100 followed by '%',
-for example, `offset=20%' to specify 20%. In ZBD mode, value can be set as
+for example, `offset=20%' to specify 20%. In ZBD mode, value can be set as
number of zones using 'z'.
.TP
.BI offset_align \fR=\fPint
intended to operate on a file in parallel disjoint segments, with even
spacing between the starting points. Percentages can be used for this option.
If a percentage is given, the generated offset will be aligned to the minimum
-\fBblocksize\fR or to the value of \fBoffset_align\fR if provided.In ZBD mode, value
+\fBblocksize\fR or to the value of \fBoffset_align\fR if provided.In ZBD mode, value
can be set as number of zones using 'z'.
.TP
.BI number_ios \fR=\fPint
files or devices. If the files do not exist, size 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. In ZBD mode,
-size can be given in units of number of zones using 'z'. Can be combined with \fBoffset\fR to
+size can be given in units of number of zones using 'z'. Can be combined with \fBoffset\fR to
constrain the start and end range that I/O will be done within.
.TP
.BI io_size \fR=\fPint[%|z] "\fR,\fB io_limit" \fR=\fPint[%|z]
.BI filesize \fR=\fPirange(int)
Individual file sizes. May be a range, in which case fio will select sizes
for files at random within the given range. If not given, each created file
-is the same size. This option overrides \fBsize\fR in terms of file size,
+is the same size. This option overrides \fBsize\fR in terms of file size,
i.e. \fBsize\fR becomes merely the default for \fBio_size\fR (and
has no effect it all if \fBio_size\fR is set explicitly).
.TP
.B pvsync2
Basic \fBpreadv2\fR\|(2) or \fBpwritev2\fR\|(2) I/O.
.TP
+.B io_uring
+Fast Linux native asynchronous I/O. Supports async IO
+for both direct and buffered IO.
+This engine defines engine specific options.
+.TP
+.B io_uring_cmd
+Fast Linux native asynchronous I/O for passthrough commands.
+This engine defines engine specific options.
+.TP
.B libaio
Linux native asynchronous I/O. Note that Linux may only support
queued behavior with non-buffered I/O (set `direct=1' or
\fBcmdprio_percentage\fR option.
.RE
.TP
-.BI (io_uring)fixedbufs
+.BI (io_uring,io_uring_cmd)fixedbufs
If fio is asked to do direct IO, then Linux will map pages for each IO call, and
release them when IO is done. If this option is set, the pages are pre-mapped
before IO is started. This eliminates the need to map and release for each IO.
This is more efficient, and reduces the IO latency as well.
.TP
-.BI (io_uring,xnvme)hipri
+.BI (io_uring,io_uring_cmd)nonvectored
+With this option, fio will use non-vectored read/write commands, where address
+must contain the address directly. Default is -1.
+.TP
+.BI (io_uring,io_uring_cmd)force_async
+Normal operation for io_uring is to try and issue an sqe as non-blocking first,
+and if that fails, execute it in an async manner. With this option set to N,
+then every N request fio will ask sqe to be issued in an async manner. Default
+is 0.
+.TP
+.BI (io_uring,io_uring_cmd,xnvme)hipri
If this option is set, fio will attempt to use polled IO completions. Normal IO
completions generate interrupts to signal the completion of IO, polled
completions do not. Hence they are require active reaping by the application.
The benefits are more efficient IO for high IOPS scenarios, and lower latencies
for low queue depth IO.
.TP
-.BI (io_uring)registerfiles
+.BI (io_uring,io_uring_cmd)registerfiles
With this option, fio registers the set of files being used with the kernel.
This avoids the overhead of managing file counts in the kernel, making the
submission and completion part more lightweight. Required for the below
sqthread_poll option.
.TP
-.BI (io_uring,xnvme)sqthread_poll
+.BI (io_uring,io_uring_cmd,xnvme)sqthread_poll
Normally fio will submit IO by issuing a system call to notify the kernel of
available items in the SQ ring. If this option is set, the act of submitting IO
will be done by a polling thread in the kernel. This frees up cycles for fio, at
the cost of using more CPU in the system.
.TP
-.BI (io_uring)sqthread_poll_cpu
+.BI (io_uring,io_uring_cmd)sqthread_poll_cpu
When `sqthread_poll` is set, this option provides a way to define which CPU
should be used for the polling thread.
.TP
+.BI (io_uring_cmd)cmd_type \fR=\fPstr
+Specifies the type of uring passthrough command to be used. Supported
+value is nvme. Default is nvme.
+.TP
.BI (libaio)userspace_reap
Normally, with the libaio engine in use, fio will use the
\fBio_getevents\fR\|(3) system call to reap newly returned events. With
the full *type.id* string. If no type. prefix is given, fio will add 'client.'
by default.
.TP
+.BI (rados)conf \fR=\fPstr
+Specifies the configuration path of ceph cluster, so conf file does not
+have to be /etc/ceph/ceph.conf.
+.TP
.BI (rbd,rados)busy_poll \fR=\fPbool
Poll store instead of waiting for completion. Usually this provides better
throughput at cost of higher(up to 100%) CPU utilization.
.BI (http)http_s3_keyid \fR=\fPstr
The S3 key/access id.
.TP
+.BI (http)http_s3_sse_customer_key \fR=\fPstr
+The encryption customer key in SSE server side.
+.TP
+.BI (http)http_s3_sse_customer_algorithm \fR=\fPstr
+The encryption customer algorithm in SSE server side. Default is \fBAES256\fR
+.TP
+.BI (http)http_s3_storage_class \fR=\fPstr
+Which storage class to access. User-customizable settings. Default is \fBSTANDARD\fR
+.TP
.BI (http)http_swift_auth_token \fR=\fPstr
The Swift auth token. See the example configuration file on how to
retrieve this.
Specify the label or UUID of the DAOS container to open.
.TP
.BI (dfs)chunk_size
-Specificy a different chunk size (in bytes) for the dfs file.
+Specify a different chunk size (in bytes) for the dfs file.
Use DAOS container's chunk size by default.
.TP
.BI (dfs)object_class
-Specificy a different object class for the dfs file.
+Specify a different object class for the dfs file.
Use DAOS container's object class by default.
.TP
.BI (nfs)nfs_url
.RS
.TP
.B emu
-This is default and used to emulate asynchronous I/O
+This is default and use to emulate asynchronous I/O by using a single thread to
+create a queue pair on top of a synchronous I/O interface using the NVMe driver
+IOCTL.
.TP
.BI thrpool
-Use thread pool for Asynchronous I/O
+Emulate an asynchronous I/O interface with a pool of userspace threads on top
+of a synchronous I/O interface using the NVMe driver IOCTL. By default four
+threads are used.
.TP
.BI io_uring
-Use Linux io_uring/liburing for Asynchronous I/O
+Linux native asynchronous I/O interface which supports both direct and buffered
+I/O.
.TP
.BI libaio
Use Linux aio for Asynchronous I/O
.TP
.BI posix
-Use POSIX aio for Asynchronous I/O
+Use the posix asynchronous I/O interface to perform one or more I/O operations
+asynchronously.
.TP
.BI nil
-Use nil-io; For introspective perf. evaluation
+Do not transfer any data; just pretend to. This is mainly used for
+introspective performance evaluation.
.RE
.RE
.TP
.RS
.TP
.B nvme
-This is default and uses Linux NVMe Driver ioctl() for synchronous I/O
+This is default and uses Linux NVMe Driver ioctl() for synchronous I/O.
.TP
.BI psync
-Use pread()/write() for synchronous I/O
+This supports regular as well as vectored pread() and pwrite() commands.
+.TP
+.BI block
+This is the same as psync except that it also supports zone management
+commands using Linux block layer IOCTLs.
.RE
.RE
.TP
.RS
.TP
.B nvme
-This is default and uses Linux NVMe Driver ioctl() for admin commands
+This is default and uses Linux NVMe Driver ioctl() for admin commands.
.TP
.BI block
-Use Linux Block Layer ioctl() and sysfs for admin commands
-.TP
-.BI file_as_ns
-Use file-stat as to construct NVMe idfy responses
+Use Linux Block Layer ioctl() and sysfs for admin commands.
.RE
.RE
.TP
.BI (xnvme)xnvme_dev_nsid\fR=\fPint
-xnvme namespace identifier, for userspace NVMe driver.
+xnvme namespace identifier for userspace NVMe driver such as SPDK.
.TP
.BI (xnvme)xnvme_iovec
If this option is set, xnvme will use vectored read/write commands.
.BI write_iolog \fR=\fPstr
Write the issued I/O patterns to the specified file. See
\fBread_iolog\fR. Specify a separate file for each job, otherwise the
-iologs will be interspersed and the file may be corrupt.
+iologs will be interspersed and the file may be corrupt. This file will be
+opened in append mode.
.TP
.BI read_iolog \fR=\fPstr
Open an iolog with the specified filename and replay the I/O patterns it
completed. If this option is used, there are two more stats that are
appended, the total error count and the first error. The error field given
in the stats is the first error that was hit during the run.
+.RS
+.P
+Note: a write error from the device may go unnoticed by fio when using buffered
+IO, as the write() (or similar) system call merely dirties the kernel pages,
+unless `sync' or `direct' is used. Device IO errors occur when the dirty data is
+actually written out to disk. If fully sync writes aren't desirable, `fsync' or
+`fdatasync' can be used as well. This is specific to writes, as reads are always
+synchronous.
+.RS
+.P
The allowed values are:
.RS
.RS
projects / fio.git / blobdiff