Fix typo in bssplit documentation

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index 8ee00fd1210dbf7089f5b58b270f46ebb41c2721..4398ffa717843095889b8d2065d5a05769a50acb 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -1429,7 +1429,7 @@ Block size
        If you want a workload that has 50% 2k reads and 50% 4k reads, while
        having 90% 4k writes and 10% 8k writes, you would specify::
 
-               bssplit=2k/50:4k/50,4k/90,8k/10
+               bssplit=2k/50:4k/50,4k/90:8k/10
 
        Fio supports defining up to 64 different weights for each data
        direction.
@@ -2079,6 +2079,26 @@ with the caveat that when used on the command line, they must come after the
        With writefua option set to 1, write operations include
        the force unit access (fua) flag. Default is 0.
 
+.. option:: sg_write_mode=str : [sg]
+       Specify the type of write commands to issue. This option can take three values:
+
+       **write**
+               This is the default where write opcodes are issued as usual.
+       **verify**
+               Issue WRITE AND VERIFY commands. The BYTCHK bit is set to 0. This
+               directs the device to carry out a medium verification with no data
+               comparison. The writefua option is ignored with this selection.
+       **same**
+               Issue WRITE SAME commands. This transfers a single block to the device
+               and writes this same block of data to a contiguous sequence of LBAs
+               beginning at the specified offset. fio's block size parameter specifies
+               the amount of data written with each command. However, the amount of data
+               actually transferred to the device is equal to the device's block
+               (sector) size. For a device with 512 byte sectors, blocksize=8k will
+               write 16 sectors with each command. fio will still generate 8k of data
+               for each command but only the first 512 bytes will be used and
+               transferred to the device. The writefua option is ignored with this
+               selection.
 
 I/O depth
 ~~~~~~~~~
@@ -2346,6 +2366,14 @@ I/O replay
 
        Scale sector offsets down by this factor when replaying traces.
 
+.. option:: replay_skip=str
+
+       Sometimes it's useful to skip certain IO types in a replay trace.
+       This could be, for instance, eliminating the writes in the trace.
+       Or not replaying the trims/discards, if you are redirecting to
+       a device that doesn't support them. This option takes a comma
+       separated list of read, write, trim, sync.
+
 
 Threads, processes and job synchronization
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~