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>
This commit is contained in:
Philipp Reisner 2010-05-04 16:57:18 +02:00
parent bd26bfc5b4
commit cdd67a7460

View File

@ -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);