Update fio io engine version

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index 8312d9315ae3a591b7a85cdd0822c86626ace840..7cab05379f612034abdc173f03acb8d7850f902f 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -555,10 +555,22 @@ verify=str        If writing to a file, fio can verify the file contents
                        crc32   Use a crc32 sum of the data area and store
                                it in the header of each block.
 
+                       null    Only pretend to verify. Useful for testing
+                               internals with ioengine=null, not for much
+                               else.
+
                This option can be used for repeated burn-in tests of a
                system to make sure that the written data is also
                correctly read back.
 
+verifysort=bool        If set, fio will sort written verify blocks when it deems
+               it faster to read them back in a sorted manner. This is
+               often the case when overwriting an existing file, since
+               the blocks are already laid out in the file system. You
+               can ignore this option unless doing huge amounts of really
+               fast IO where the red-black tree sorting CPU time becomes
+               significant.
+               
 stonewall      Wait for preceeding jobs in the job file to exit, before
                starting this one. Can be used to insert serialization
                points in the job file. A stone wall also implies starting