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.
+.TP
+.B randtrimwrite
+Like
+.B trimwrite ,
+but uses random offsets rather than sequential writes.
.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
.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.
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