diff options
| author | Lars Ellenberg <lars.ellenberg@linbit.com> | 2013-12-20 14:22:13 +0400 |
|---|---|---|
| committer | Philipp Reisner <philipp.reisner@linbit.com> | 2014-07-10 20:35:13 +0400 |
| commit | ad3fee790088d36ad862e31535b5b99c25adeef4 (patch) | |
| tree | 916a5c23cf57283f9f6a5abf8418364c52249ad9 /drivers/block/drbd/drbd_req.c | |
| parent | 7753a4c17f9e305ed19d8851e1a3154c8c9abaaf (diff) | |
| download | linux-ad3fee790088d36ad862e31535b5b99c25adeef4.tar.xz | |
drbd: improve throttling decisions of background resynchronisation
Background resynchronisation does some "side-stepping", or throttles
itself, if it detects application IO activity, and the current resync
rate estimate is above the configured "cmin-rate".
What was not detected: if there is no application IO,
because it blocks on activity log transactions.
Introduce a new atomic_t ap_actlog_cnt, tracking such blocked requests,
and count non-zero as application IO activity.
This counter is exposed at proc_details level 2 and above.
Also make sure to release the currently locked resync extent
if we side-step due to such voluntary throttling.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Diffstat (limited to 'drivers/block/drbd/drbd_req.c')
| -rw-r--r-- | drivers/block/drbd/drbd_req.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c index 3f6a6ed2fd03..74ebef101dc7 100644 --- a/drivers/block/drbd/drbd_req.c +++ b/drivers/block/drbd/drbd_req.c @@ -1218,6 +1218,7 @@ drbd_request_prepare(struct drbd_device *device, struct bio *bio, unsigned long if (rw == WRITE && req->private_bio && req->i.size && !test_bit(AL_SUSPENDED, &device->flags)) { if (!drbd_al_begin_io_fastpath(device, &req->i)) { + atomic_inc(&device->ap_actlog_cnt); drbd_queue_write(device, req); return NULL; } @@ -1354,6 +1355,7 @@ static void submit_fast_path(struct drbd_device *device, struct list_head *incom req->rq_state |= RQ_IN_ACT_LOG; req->in_actlog_jif = jiffies; + atomic_dec(&device->ap_actlog_cnt); } list_del_init(&req->tl_requests); @@ -1439,6 +1441,7 @@ skip_fast_path: list_for_each_entry_safe(req, tmp, &pending, tl_requests) { req->rq_state |= RQ_IN_ACT_LOG; req->in_actlog_jif = jiffies; + atomic_dec(&device->ap_actlog_cnt); list_del_init(&req->tl_requests); drbd_send_and_submit(device, req); } @@ -1454,6 +1457,7 @@ skip_fast_path: if (!was_cold) { req->rq_state |= RQ_IN_ACT_LOG; req->in_actlog_jif = jiffies; + atomic_dec(&device->ap_actlog_cnt); /* Corresponding extent was hot after all? */ drbd_send_and_submit(device, req); } else { |