Improve random verify block sorting
Add an option to control it and also check the nosort flag in file
layout to further catch a case where sorting isn't needed.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/HOWTO b/HOWTO
index a5be9db..7cab053 100644
--- a/HOWTO
+++ b/HOWTO
@@ -563,6 +563,14 @@
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