diff options
| author | Lars Ellenberg <lars.ellenberg@linbit.com> | 2014-03-18 12:30:09 +0100 |
|---|---|---|
| committer | Philipp Reisner <philipp.reisner@linbit.com> | 2014-07-10 18:35:00 +0200 |
| commit | aaaba34576407857f6146ff6c330f06e63fb2bf2 (patch) | |
| tree | 6cd468ecb123314d06c641185410f6cbce58c504 /drivers/block/drbd/drbd_receiver.c | |
| parent | 6a8d68b1878e8839b4927150da236c8248703c70 (diff) | |
drbd: implement csums-after-crash-only
Checksum based resync trades CPU cycles for network bandwidth,
in situations where we expect much of the to-be-resynced blocks
to be actually identical on both sides already.
In a "network hickup" scenario, it won't help:
all to-be-resynced blocks will typically be different.
The use case is for the resync of *potentially* different blocks
after crash recovery -- the crash recovery had marked larger areas
(those covered by the activity log) as need-to-be-resynced,
just in case. Most of those blocks will be identical.
This option makes it possible to configure checksum based resync,
but only actually use it for the first resync after primary crash.
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_receiver.c')
| -rw-r--r-- | drivers/block/drbd/drbd_receiver.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c index 5626c5babc3f..d326af67c27e 100644 --- a/drivers/block/drbd/drbd_receiver.c +++ b/drivers/block/drbd/drbd_receiver.c @@ -2555,6 +2555,8 @@ static int receive_DataRequest(struct drbd_connection *connection, struct packet peer_req->w.cb = w_e_end_csum_rs_req; /* used in the sector offset progress display */ device->bm_resync_fo = BM_SECT_TO_BIT(sector); + /* remember to report stats in drbd_resync_finished */ + device->use_csums = true; } else if (pi->cmd == P_OV_REPLY) { /* track progress, we may need to throttle */ atomic_add(size >> 9, &device->rs_sect_in); |