drbd: allow larger max_discard_sectors
Make sure we have at least 67 (> AL_UPDATES_PER_TRANSACTION)
al-extents available, and allow up to half of that to be
discarded in one bio.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/include/linux/drbd_limits.h b/include/linux/drbd_limits.h
index a351c40..ddac684 100644
--- a/include/linux/drbd_limits.h
+++ b/include/linux/drbd_limits.h
@@ -126,8 +126,7 @@
#define DRBD_RESYNC_RATE_DEF 250
#define DRBD_RESYNC_RATE_SCALE 'k' /* kilobytes */
- /* less than 7 would hit performance unnecessarily. */
-#define DRBD_AL_EXTENTS_MIN 7
+#define DRBD_AL_EXTENTS_MIN 67
/* we use u16 as "slot number", (u16)~0 is "FREE".
* If you use >= 292 kB on-disk ring buffer,
* this is the maximum you can use: */