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authorPhilipp Reisner <philipp.reisner@linbit.com>2010-05-04 16:57:18 +0200
committerPhilipp Reisner <philipp.reisner@linbit.com>2010-05-18 01:25:47 +0200
commitcdd67a74603d0453ddffc24c572aed2ddd1795b8 (patch)
treed2a478bf8b225540044895ccf5b3b1575cc8bbd4 /drivers/block/drbd
parentbd26bfc5b4253425d17aa49648ae1f3e976041c4 (diff)
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drbd: Control the actual resync rate based on the queuing delay of data packets
In a setup with a high bandwidth and high latency network, eventually involving deep queues in routers, it is beneficial to only fill those queues up to an limited extend with resync data. Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com> Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Diffstat (limited to 'drivers/block/drbd')
-rw-r--r--drivers/block/drbd/drbd_worker.c15
1 files changed, 14 insertions, 1 deletions
diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index 44bf6d1..0bbecf4 100644
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -414,6 +414,18 @@ void resync_timer_fn(unsigned long data)
drbd_queue_work(&mdev->data.work, &mdev->resync_work);
}
+static int calc_resync_rate(struct drbd_conf *mdev)
+{
+ int d = mdev->data_delay / 1000; /* us -> ms */
+ int td = mdev->sync_conf.throttle_th * 100; /* 0.1s -> ms */
+ int hd = mdev->sync_conf.hold_off_th * 100; /* 0.1s -> ms */
+ int cr = mdev->sync_conf.rate;
+
+ return d <= td ? cr :
+ d >= hd ? 0 :
+ cr + (cr * (td - d) / (hd - td));
+}
+
int w_make_resync_request(struct drbd_conf *mdev,
struct drbd_work *w, int cancel)
{
@@ -446,7 +458,8 @@ int w_make_resync_request(struct drbd_conf *mdev,
return 1;
}
- number = SLEEP_TIME * mdev->sync_conf.rate / ((BM_BLOCK_SIZE/1024)*HZ);
+ mdev->c_sync_rate = calc_resync_rate(mdev);
+ number = SLEEP_TIME * mdev->c_sync_rate / ((BM_BLOCK_SIZE / 1024) * HZ);
pe = atomic_read(&mdev->rs_pending_cnt);
mutex_lock(&mdev->data.mutex);