vdev_disk: default to classic submission for 2.2.x

We don't want to change to brand-new code in the middle of a stable
series, but we want it available to test for people running into page
splitting issues.

This commits make zfs_vdev_disk_classic=1 the default, and updates the
documentation to better explain what's going on.

Signed-off-by: Rob Norris <rob.norris@klarasystems.com>
Sponsored-by: Klara, Inc.
Sponsored-by: Wasabi Technology, Inc.
This commit is contained in:
Rob Norris
2024-03-27 13:11:12 +11:00
committed by Brian Behlendorf
parent d0b3be763f
commit eebf00bee9
2 changed files with 27 additions and 12 deletions
+5 -3
View File
@@ -969,8 +969,10 @@ vdev_disk_io_rw(zio_t *zio)
/*
* This is the classic, battle-tested BIO submission code. Until we're totally
* sure that the new code is safe and correct in all cases, this will remain
* available and can be enabled by setting zfs_vdev_disk_classic=1 at module
* load time.
* available.
*
* It is enabled by setting zfs_vdev_disk_classic=1 at module load time. It is
* enabled (=1) by default since 2.2.4, and disabled by default (=0) on master.
*
* These functions have been renamed to vdev_classic_* to make it clear what
* they belong to, but their implementations are unchanged.
@@ -1468,7 +1470,7 @@ vdev_disk_rele(vdev_t *vd)
* BIO submission method. See comment above about vdev_classic.
* Set zfs_vdev_disk_classic=0 for new, =1 for classic
*/
static uint_t zfs_vdev_disk_classic = 0; /* default new */
static uint_t zfs_vdev_disk_classic = 1; /* default classic */
/* Set submission function from module parameter */
static int