drbd: new configuration parameter c-min-rate
We now track the data rate of locally submitted resync related requests,
and can thus detect non-resync activity on the lower level device.
If the current sync rate is above c-min-rate, and the lower level device
appears to be busy, we throttle the resyncer.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index f5d779b..99c937a 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -215,10 +215,8 @@
*/
void drbd_endio_pri(struct bio *bio, int error)
{
- unsigned long flags;
struct drbd_request *req = bio->bi_private;
struct drbd_conf *mdev = req->mdev;
- struct bio_and_error m;
enum drbd_req_event what;
int uptodate = bio_flagged(bio, BIO_UPTODATE);
@@ -244,12 +242,7 @@
bio_put(req->private_bio);
req->private_bio = ERR_PTR(error);
- spin_lock_irqsave(&mdev->req_lock, flags);
- __req_mod(req, what, &m);
- spin_unlock_irqrestore(&mdev->req_lock, flags);
-
- if (m.bio)
- complete_master_bio(mdev, &m);
+ req_mod(req, what);
}
int w_read_retry_remote(struct drbd_conf *mdev, struct drbd_work *w, int cancel)
@@ -376,6 +369,9 @@
if (!get_ldev(mdev))
return -EIO;
+ if (drbd_rs_should_slow_down(mdev))
+ goto defer;
+
/* GFP_TRY, because if there is no memory available right now, this may
* be rescheduled for later. It is "only" background resync, after all. */
e = drbd_alloc_ee(mdev, DRBD_MAGIC+0xbeef, sector, size, GFP_TRY);
@@ -387,6 +383,7 @@
list_add(&e->w.list, &mdev->read_ee);
spin_unlock_irq(&mdev->req_lock);
+ atomic_add(size >> 9, &mdev->rs_sect_ev);
if (drbd_submit_ee(mdev, e, READ, DRBD_FAULT_RS_RD) == 0)
return 0;
@@ -512,8 +509,9 @@
sector_t sector;
const sector_t capacity = drbd_get_capacity(mdev->this_bdev);
int max_segment_size;
- int number, i, rollback_i, size, pe, mx;
+ int number, rollback_i, size, pe, mx;
int align, queued, sndbuf;
+ int i = 0;
if (unlikely(cancel))
return 1;
@@ -549,7 +547,14 @@
mdev->c_sync_rate = mdev->sync_conf.rate;
number = SLEEP_TIME * mdev->c_sync_rate / ((BM_BLOCK_SIZE / 1024) * HZ);
}
- pe = atomic_read(&mdev->rs_pending_cnt);
+
+ /* Throttle resync on lower level disk activity, which may also be
+ * caused by application IO on Primary/SyncTarget.
+ * Keep this after the call to drbd_rs_controller, as that assumes
+ * to be called as precisely as possible every SLEEP_TIME,
+ * and would be confused otherwise. */
+ if (drbd_rs_should_slow_down(mdev))
+ goto requeue;
mutex_lock(&mdev->data.mutex);
if (mdev->data.socket)
@@ -563,6 +568,7 @@
mx = number;
/* Limit the number of pending RS requests to no more than the peer's receive buffer */
+ pe = atomic_read(&mdev->rs_pending_cnt);
if ((pe + number) > mx) {
number = mx - pe;
}
@@ -1492,6 +1498,8 @@
mdev->rs_failed = 0;
mdev->rs_paused = 0;
mdev->rs_same_csum = 0;
+ mdev->rs_last_events = 0;
+ mdev->rs_last_sect_ev = 0;
mdev->rs_total = tw;
mdev->rs_start = now;
for (i = 0; i < DRBD_SYNC_MARKS; i++) {
@@ -1516,6 +1524,7 @@
}
atomic_set(&mdev->rs_sect_in, 0);
+ atomic_set(&mdev->rs_sect_ev, 0);
mdev->rs_in_flight = 0;
mdev->rs_planed = 0;
spin_lock(&mdev->peer_seq_lock);