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>
This commit is contained in:
Lars Ellenberg 2016-06-14 00:26:23 +02:00 committed by Jens Axboe
parent 7435e9018f
commit 505675f96c
3 changed files with 6 additions and 7 deletions

View File

@ -258,7 +258,7 @@ bool drbd_al_begin_io_fastpath(struct drbd_device *device, struct drbd_interval
unsigned first = i->sector >> (AL_EXTENT_SHIFT-9);
unsigned last = i->size == 0 ? first : (i->sector + (i->size >> 9) - 1) >> (AL_EXTENT_SHIFT-9);
D_ASSERT(device, (unsigned)(last - first) <= 1);
D_ASSERT(device, first <= last);
D_ASSERT(device, atomic_read(&device->local_cnt) > 0);
/* FIXME figure out a fast path for bios crossing AL extent boundaries */

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@ -1347,10 +1347,10 @@ struct bm_extent {
#define DRBD_MAX_SIZE_H80_PACKET (1U << 15) /* Header 80 only allows packets up to 32KiB data */
#define DRBD_MAX_BIO_SIZE_P95 (1U << 17) /* Protocol 95 to 99 allows bios up to 128KiB */
/* For now, don't allow more than one activity log extent worth of data
* to be discarded in one go. We may need to rework drbd_al_begin_io()
* to allow for even larger discard ranges */
#define DRBD_MAX_DISCARD_SIZE AL_EXTENT_SIZE
/* For now, don't allow more than half of what we can "activate" in one
* activity log transaction to be discarded in one go. We may need to rework
* drbd_al_begin_io() to allow for even larger discard ranges */
#define DRBD_MAX_DISCARD_SIZE (AL_UPDATES_PER_TRANSACTION/2*AL_EXTENT_SIZE)
#define DRBD_MAX_DISCARD_SECTORS (DRBD_MAX_DISCARD_SIZE >> 9)
extern int drbd_bm_init(struct drbd_device *device);

View File

@ -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: */