Merge branch 'winfio'

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index 9ae34b976c78043d5df8126d5b5a918d7a09f40c..1915bd696feecf56f1cbbcda46ce3569e98980e0 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -351,7 +351,8 @@ randrepeat=bool     For random IO workloads, seed the generator in a predictable
 fallocate=bool By default, fio will use fallocate() to advise the system
                of the size of the file we are going to write. This can be
                turned off with fallocate=0. May not be available on all
-               supported platforms.
+               supported platforms.  If using ZFS on Solaris this must be
+               set to 0 because ZFS doesn't support it.
 
 fadvise_hint=bool By default, fio will use fadvise() to advise the kernel
                on what IO patterns it is likely to issue. Sometimes you
@@ -555,7 +556,7 @@ iodepth=int This defines how many io units to keep in flight against
                job, can be overridden with a larger value for higher
                concurrency. Note that increasing iodepth beyond 1 will not
                affect synchronous ioengines (except for small degress when
-               verify_async is in use). Even async engines my impose OS
+               verify_async is in use). Even async engines may impose OS
                restrictions causing the desired depth not to be achieved.
                This may happen on Linux when using libaio and not setting
                direct=1, since buffered IO is not async on that OS. Keep an
@@ -585,7 +586,7 @@ iodepth_low=int     The low water mark indicating when to start filling
                the depth drain down to 4 before starting to fill it again.
 
 direct=bool    If value is true, use non-buffered io. This is usually
-               O_DIRECT.
+               O_DIRECT. Note that ZFS on Solaris doesn't support direct io.
 
 buffered=bool  If value is true, use buffered io. This is the opposite
                of the 'direct' option. Defaults to true.