.TP
.B randrw
Mixed random reads and writes.
+.TP
+.B trimwrite
+Trim and write mixed workload. Blocks will be trimmed first, then the same
+blocks will be written to.
.RE
.P
For mixed I/O, the default split is 50/50. For certain types of io the result
Use \fBposix_fadvise\fR\|(2) to advise the kernel what I/O patterns
are likely to be issued. Default: true.
.TP
+.BI fadvise_stream \fR=\fPint
+Use \fBposix_fadvise\fR\|(2) to advise the kernel what stream ID the
+writes issued belong to. Only supported on Linux. Note, this option
+may change going forward.
+.TP
.BI size \fR=\fPint
Total size of I/O for this job. \fBfio\fR will run until this many bytes have
been transferred, unless limited by other options (\fBruntime\fR, for instance,
.TP
.B zero_buffers
Initialize buffers with all zeros. Default: fill buffers with random data.
-The resulting IO buffers will not be completely zeroed, unless
-\fPscramble_buffers\fR is also turned off.
.TP
.B refill_buffers
If this option is given, fio will refill the IO buffers on every submit. The
example job file to create such files, use rw=write option). Please note, you
might want to set necessary environment variables to work with hdfs/libhdfs
properly.
+.TP
+.B mtd
+Read, write and erase an MTD character device (e.g., /dev/mtd0). Discards are
+treated as erases. Depending on the underlying device type, the I/O may have
+to go in a certain pattern, e.g., on NAND, writing sequentially to erase blocks
+and discarding before overwriting. The writetrim mode works well for this
+constraint.
.RE
.P
.RE
Low watermark indicating when to start filling the queue again. Default:
\fBiodepth\fR.
.TP
+.BI io_submit_mode \fR=\fPstr
+This option controls how fio submits the IO to the IO engine. The default is
+\fBinline\fR, which means that the fio job threads submit and reap IO directly.
+If set to \fBoffload\fR, the job threads will offload IO submission to a
+dedicated pool of IO threads. This requires some coordination and thus has a
+bit of extra overhead, especially for lower queue depth IO where it can
+increase latencies. The benefit is that fio can manage submission rates
+independently of the device completion rates. This avoids skewed latency
+reporting if IO gets back up on the device side (the coordinated omission
+problem).
+.TP
.BI direct \fR=\fPbool
If true, use non-buffered I/O (usually O_DIRECT). Default: false.
.TP
\fB\-\-inflate-log\fR command line parameter. The files will be stored with a
\fB\.fz\fR suffix.
.TP
+.BI block_error_percentiles \fR=\fPbool
+If set, record errors in trim block-sized units from writes and trims and output
+a histogram of how many trims it took to get to errors, and what kind of error
+was encountered.
+.TP
.BI disable_lat \fR=\fPbool
Disable measurements of total latency numbers. Useful only for cutting
back the number of calls to \fBgettimeofday\fR\|(2), as that does impact performance at
Enable the reporting of percentiles of completion latencies.
.TP
.BI percentile_list \fR=\fPfloat_list
-Overwrite the default list of percentiles for completion
-latencies. Each number is a floating number in the range (0,100], and
-the maximum length of the list is 20. Use ':' to separate the
+Overwrite the default list of percentiles for completion latencies and the
+block error histogram. Each number is a floating number in the range (0,100],
+and the maximum length of the list is 20. Use ':' to separate the
numbers. For example, \-\-percentile_list=99.5:99.9 will cause fio to
report the values of completion latency below which 99.5% and 99.9% of
the observed latencies fell, respectively.
.TP
.BI (rbd)clientname \fR=\fPstr
Specifies the username (without the 'client.' prefix) used to access the Ceph cluster.
+.TP
+.BI (mtd)skipbad \fR=\fPbool
+Skip operations against known bad blocks.
.SH OUTPUT
While running, \fBfio\fR will display the status of the created jobs. For
example: