Fix blkparse typo

[fio.git] / HOWTO

diff --git a/HOWTO b/HOWTO
index 91a1ec353cf3180168ea7352b8a506c94b04ed99..19304aefc87d92bc6fd17a3fd28f6768c79f8550 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -566,8 +566,24 @@ fsync=int  If writing to a file, issue a sync of the dirty data
                not sync the file. The exception is the sg io engine, which
                synchronizes the disk cache anyway.
 
-fsyncdata=int  Like fsync= but uses fdatasync() to only sync data and not
+fdatasync=int  Like fsync= but uses fdatasync() to only sync data and not
                metadata blocks.
+               In FreeBSD there is no fdatasync(), this falls back to
+               using fsync()
+
+sync_file_range=str:val        Use sync_file_range() for every 'val' number of
+               write operations. Fio will track range of writes that
+               have happened since the last sync_file_range() call. 'str'
+               can currently be one or more of:
+
+               wait_before     SYNC_FILE_RANGE_WAIT_BEFORE
+               write           SYNC_FILE_RANGE_WRITE
+               wait_after      SYNC_FILE_RANGE_WAIT_AFTER
+
+               So if you do sync_file_range=wait_before,write:8, fio would
+               use SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE for
+               every 8 writes. Also see the sync_file_range(2) man page.
+               This option is Linux specific.
 
 overwrite=bool If true, writes to a file will always overwrite existing
                data. If the file doesn't already exist, it will be
@@ -926,7 +942,7 @@ read_iolog=str      Open an iolog with the specified file name and replay the
                to replay a workload captured by blktrace. See blktrace
                for how to capture such logging data. For blktrace replay,
                the file needs to be turned into a blkparse binary data
-               file first (blktrace <device> -d file_for_fio.bin).
+               file first (blkparse <device> -o /dev/null -d file_for_fio.bin).
 
 write_bw_log=str If given, write a bandwidth log of the jobs in this job
                file. Can be used to store data of the bandwidth of the
@@ -1020,6 +1036,12 @@ cgroup_weight=int        Set the weight of the cgroup to this value. See
                the documentation that comes with the kernel, allowed values
                are in the range of 100..1000.
 
+cgroup_nodelete=bool Normally fio will delete the cgroups it has created after
+               the job completion. To override this behavior and to leave
+               cgroups around after the job completion, set cgroup_nodelete=1.
+               This can be useful if one wants to inspect various cgroup
+               files after job completion. Default: false
+
 uid=int                Instead of running as the invoking user, set the user ID to
                this value before the thread/process does any work.