Merge branch 'chunked-iolog-reading' of https://github.com/aclamk/fio

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index 70eed2805c2d96811d4238afaed645f4f3a10e45..16c5ae3163074fcb08a6caca741cb78a0b56c29b 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -991,13 +991,15 @@ I/O type
                **write**
                                Sequential writes.
                **trim**
-                               Sequential trims (Linux block devices only).
+                               Sequential trims (Linux block devices and SCSI
+                               character devices only).
                **randread**
                                Random reads.
                **randwrite**
                                Random writes.
                **randtrim**
-                               Random trims (Linux block devices only).
+                               Random trims (Linux block devices and SCSI
+                               character devices only).
                **rw,readwrite**
                                Sequential mixed reads and writes.
                **randrw**
@@ -1748,7 +1750,7 @@ I/O engine
                        ioctl, or if the target is an sg character device we use
                        :manpage:`read(2)` and :manpage:`write(2)` for asynchronous
                        I/O. Requires :option:`filename` option to specify either block or
-                       character devices.
+                       character devices. This engine supports trim operations.
                        The sg engine includes engine specific options.
 
                **null**
@@ -2082,6 +2084,7 @@ with the caveat that when used on the command line, they must come after the
        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**
@@ -2324,6 +2327,12 @@ I/O replay
        replay, the file needs to be turned into a blkparse binary data file first
        (``blkparse <device> -o /dev/null -d file_for_fio.bin``).
 
+.. option:: read_iolog_chunked=bool
+
+       Determines how iolog is read. If false(default) entire :option:`read_iolog`
+       will be read at once. If selected true, input from iolog will be read
+       gradually. Useful when iolog is very large, or it is generated.
+
 .. option:: replay_no_stall=bool
 
        When replaying I/O with :option:`read_iolog` the default behavior is to