ext4: Add mount option to set kjournald's I/O priority
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jens Axboe <jens.axboe@oracle.com>
diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt
index 9ec29d8..8938949 100644
--- a/Documentation/filesystems/ext4.txt
+++ b/Documentation/filesystems/ext4.txt
@@ -308,6 +308,13 @@
multi-threaded, synchronous workloads on very
fast disks, at the cost of increasing latency.
+journal_ioprio=prio The I/O priority (from 0 to 7, where 0 is the
+ highest priorty) which should be used for I/O
+ operations submitted by kjournald2 during a
+ commit operation. This defaults to 3, which is
+ a slightly higher priority than the default I/O
+ priority.
+
Data Mode
=========
There are 3 different data modes: