Note: Windows and FreeBSD prevent write access to areas
of the disk containing in-use data (e.g. filesystems).
.P
+For HTTP and S3 access, specify a valid URL path or S3 key, respectively.
+A filename for path-style S3 includes a bucket name (`/bucket/k/e.y')
+while a virtual-hosted-style S3 filename (`/k/e.y') does not because its
+bucket name is specified in \fBhttp_host\fR.
+.P
The filename `\-' is a reserved name, meaning *stdin* or *stdout*. Which
of the two depends on the read/write direction set.
.RE
For direct I/O, requests will only succeed if cache invalidation isn't required,
file blocks are fully allocated and the disk request could be issued immediately.
.TP
+.BI (pvsync2,libaio,io_uring)atomic \fR=\fPbool
+This option means that writes are issued with torn-write protection, meaning
+that for a power fail or kernel crash, all or none of the data from the write
+will be stored, but never a mix of old and new data. Torn-write protection is
+also known as atomic writes.
+
+This option sets the RWF_ATOMIC flag (supported from the 6.11 Linux kernel) on
+a per-IO basis.
+
+Writes with RWF_ATOMIC set will be rejected by the kernel when the file does
+not support torn-write protection. To learn a file's torn-write limits, issue
+statx with STATX_WRITE_ATOMIC.
+.TP
.BI (io_uring_cmd,xnvme)fdp \fR=\fPbool
Enable Flexible Data Placement mode for write commands.
.TP
.RE
.TP
.BI (io_uring_cmd,xnvme)plids=str, fdp_pli \fR=\fPstr
-Select which Placement IDs (streams) or Placement ID Indicies (FDP) this job is
-allowed to use for writes. For FDP by default, the job will cycle through all
-available Placement IDs, so use this to isolate these identifiers to specific
-jobs. If you want fio to use placement identifier only at indices 0, 2 and 5
-specify, you would set `plids=0,2,5`. For streams this should be a
-comma-separated list of Stream IDs.
+Select which Placement ID Indices (FDP) or Placement IDs (streams) this job is
+allowed to use for writes. This option accepts a comma-separated list of values
+or ranges (e.g., 1,2-4,5,6-8).
+
+For FDP by default, the job will cycle through all available Placement IDs, so
+use this option to be selective. The values specified here are array indices
+for the list of placement IDs returned by the nvme-cli command `nvme fdp
+status'. If you want fio to use FDP placement identifiers only at indices 0, 2
+and 5, set `plids=0,2,5'.
+
+For streams this should be a list of Stream IDs.
.TP
.BI (io_uring_cmd,xnvme)\fR\fBdp_scheme\fP=str
Defines which placement ID (index) to be selected based on offset(LBA) range.
this will be the starting port number since fio will use a range of
ports.
.TP
-.BI (rdma,librpma_*)port \fR=\fPint
+.BI (rdma)port \fR=\fPint
The port to use for RDMA-CM communication. This should be the same
value on the client and the server side.
.TP
If the job is a TCP listener or UDP reader, the hostname is not used
and must be omitted unless it is a valid UDP multicast address.
.TP
-.BI (librpma_*)serverip \fR=\fPstr
-The IP address to be used for RDMA-CM based I/O.
-.TP
-.BI (librpma_*_server)direct_write_to_pmem \fR=\fPbool
-Set to 1 only when Direct Write to PMem from the remote host is possible. Otherwise, set to 0.
-.TP
-.BI (librpma_*_server)busy_wait_polling \fR=\fPbool
-Set to 0 to wait for completion instead of busy-wait polling completion.
-Default: 1.
-.TP
.BI (netsplice,net)interface \fR=\fPstr
The IP address of the network interface used to send or receive UDP
multicast.
Enabled by default.
.TP
.BI (http)http_host \fR=\fPstr
-Hostname to connect to. For S3, this could be the bucket name. Default
-is \fBlocalhost\fR
+Hostname to connect to. HTTP port 80 is used automatically when the value
+of the \fBhttps\fP parameter is \fRoff\fP, and HTTPS port 443 if it is \Ron\fP.
+A virtual-hosted-style S3 hostname starts with a bucket name, while a
+path-style S3 hostname does not. Default is \fBlocalhost\fR.
.TP
.BI (http)http_user \fR=\fPstr
Username for HTTP authentication.
and mq_poll). The MegaRAID driver is an example of a SCSI LLD.
Default: clear (0) which does normal (interrupted based) IO.
.TP
-.BI (sg)readfua \fR=\fPbool
+.BI (sg, io_uring_cmd)readfua \fR=\fPbool
With readfua option set to 1, read operations include the force
unit access (fua) flag. Default: 0.
.TP
-.BI (sg)writefua \fR=\fPbool
+.BI (sg, io_uring_cmd)writefua \fR=\fPbool
With writefua option set to 1, write operations include the force
unit access (fua) flag. Default: 0.
.TP
+.BI (io_uring_cmd)write_mode \fR=\fPstr
+Specifies the type of write operation. Defaults to 'write'.
+.RS
+.RS
+.TP
+.B write
+Use Write commands for write operations
+.TP
+.B uncor
+Use Write Uncorrectable commands for write operations
+.TP
+.B zeroes
+Use Write Zeroes commands for write operations
+.TP
+.B verify
+Use Verify commands for write operations
+.TP
+.RE
+.RE
+.TP
.BI (sg)sg_write_mode \fR=\fPstr
Specify the type of write commands to issue. This option can take multiple
values:
later use during the verification phase. Experimental verify instead resets the
file after the write phase and then replays I/Os for the verification phase.
.TP
+.BI verify_write_sequence \fR=\fPbool
+Verify the header write sequence number. In a scenario with multiple jobs,
+verification of the write sequence number may fail. Disabling this option
+will mean that write sequence number checking is skipped. Doing that can be
+useful for testing atomic writes, as it means that checksum verification can
+still be attempted. For when \fBatomic\fR is enabled, checksum verification
+is expected to succeed (while write sequence checking can still fail).
+.TP
.BI trim_percentage \fR=\fPint
Number of verify blocks to discard/trim.
.TP
offsets are not present in logs. Also see \fBLOG FILE FORMATS\fR section.
.TP
.BI log_prio \fR=\fPbool
-If this is set, the iolog options will include the I/O priority for the I/O
-entry as well as the other data values. Defaults to 0 meaning that
-I/O priorities are not present in logs. Also see \fBLOG FILE FORMATS\fR section.
+If this is set, the `Command priority` field in \fBLOG FILE FORMATS\fR
+shows the priority value and the IO priority class of the command.
+Otherwise, the field shows if the command has the highest RT priority
+class or not. Also see \fBLOG FILE FORMATS\fR section.
+.TP
+.BI log_issue_time \fR=\fPbool
+If this is set, the iolog options will include the command issue time for the
+I/O entry as well as the other data values. Defaults to 0 meaning that command
+issue times are not present in logs. Also see \fBLOG FILE FORMATS\fR section.
+This option shall be set together with \fBwrite_lat_log\fR and \fBlog_offset\fR.
.TP
.BI log_compression \fR=\fPint
If this is set, fio will compress the I/O logs as it goes, to keep the
.RS
.P
time (msec), value, data direction, block size (bytes), offset (bytes),
-command priority
+command priority, issue time (nsec)
.RE
.P
`Time' for the log entry is always in milliseconds. The `value' logged depends
\fBcmdprio\fR options) and the highest 3 bits indicating the IO priority class
(\fBprioclass\fR and \fBcmdprio_class\fR options).
.P
+The entry's `issue time` is the command issue time in nanoseconds. The logging
+of the issue time can be toggled with \fBlog_issue_time\fR. This field has valid
+values in completion latency log file (clat), or submit latency log file (slat).
+The field has value 0 in other log files.
+.P
Fio defaults to logging every individual I/O but when windowed logging is set
through \fBlog_avg_msec\fR, either the average (by default), the maximum
(\fBlog_window_value\fR is set to max) `value' seen over the specified period of
.RS
.P
time (msec), value, value1, data direction, block size (bytes), offset (bytes),
-command priority
+command priority, issue time (nsec)
.RE
.P
Each `data direction' seen within the window period will aggregate its values
-in a separate row. Further, when using windowed logging the `block size' and
-`offset' entries will always contain 0.
+in a separate row. Further, when using windowed logging the `block size',
+`offset' and `issue time` entries will always contain 0.
.SH CLIENT / SERVER
Normally fio is invoked as a stand-alone application on the machine where the
I/O workload should be generated. However, the backend and frontend of fio can
projects / fio.git / blobdiff