md: Update checkpoint of resync/recovery based on time.

md will current only only checkpoint recovery or resync ever 1/16th
of the device size.  As devices get larger this can become a long time
an so a lot of work that might need to be duplicated after a shutdown.

So add a time-based checkpoint.  Every 5 minutes limits the amount of
duplicated effort to at most 5 minutes, and has almost zero impact on
performance.

[changelog entry re-written by NeilBrown]

Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This commit is contained in:
majianpeng 2012-10-31 11:59:10 +11:00 committed by NeilBrown
parent 35d78c6696
commit 54f89341e8

View file

@ -7277,6 +7277,7 @@ EXPORT_SYMBOL_GPL(md_allow_write);
#define SYNC_MARKS 10
#define SYNC_MARK_STEP (3*HZ)
#define UPDATE_FREQUENCY (5*60*HZ)
void md_do_sync(struct md_thread *thread)
{
struct mddev *mddev = thread->mddev;
@ -7285,6 +7286,7 @@ void md_do_sync(struct md_thread *thread)
window;
sector_t max_sectors,j, io_sectors;
unsigned long mark[SYNC_MARKS];
unsigned long update_time;
sector_t mark_cnt[SYNC_MARKS];
int last_mark,m;
struct list_head *tmp;
@ -7444,6 +7446,7 @@ void md_do_sync(struct md_thread *thread)
mddev->curr_resync_completed = j;
sysfs_notify(&mddev->kobj, NULL, "sync_completed");
md_new_event(mddev);
update_time = jiffies;
blk_start_plug(&plug);
while (j < max_sectors) {
@ -7455,6 +7458,7 @@ void md_do_sync(struct md_thread *thread)
((mddev->curr_resync > mddev->curr_resync_completed &&
(mddev->curr_resync - mddev->curr_resync_completed)
> (max_sectors >> 4)) ||
time_after_eq(jiffies, update_time + UPDATE_FREQUENCY) ||
(j - mddev->curr_resync_completed)*2
>= mddev->resync_max - mddev->curr_resync_completed
)) {
@ -7465,6 +7469,7 @@ void md_do_sync(struct md_thread *thread)
if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) &&
j > mddev->recovery_cp)
mddev->recovery_cp = j;
update_time = jiffies;
set_bit(MD_CHANGE_CLEAN, &mddev->flags);
sysfs_notify(&mddev->kobj, NULL, "sync_completed");
}