1 files changed, 13 insertions, 4 deletions

diff --git a/drivers/md/md.c b/drivers/md/md.c
index f3fed662f32e..78c7418478d6 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -3846,11 +3846,20 @@ static int is_mddev_idle(mddev_t *mddev)
                 curr_events = disk_stat_read(disk, sectors[0]) + 
                                 disk_stat_read(disk, sectors[1]) - 
                                 atomic_read(&disk->sync_io);
-                /* Allow some slack between valud of curr_events and last_events,
-                 * as there are some uninteresting races.
+                /* The difference between curr_events and last_events
+                 * will be affected by any new non-sync IO (making
+                 * curr_events bigger) and any difference in the amount of
+                 * in-flight syncio (making current_events bigger or smaller)
+                 * The amount in-flight is currently limited to
+                 * 32*64K in raid1/10 and 256*PAGE_SIZE in raid5/6
+                 * which is at most 4096 sectors.
+                 * These numbers are fairly fragile and should be made
+                 * more robust, probably by enforcing the
+                 * 'window size' that md_do_sync sort-of uses.
+                 *
                  * Note: the following is an unsigned comparison.
                  */
-                if ((curr_events - rdev->last_events + 32) > 64) {
+                if ((curr_events - rdev->last_events + 4096) > 8192) {
                         rdev->last_events = curr_events;
                         idle = 0;
                 }
@@ -4109,7 +4118,7 @@ static void md_do_sync(mddev_t *mddev)
                 if (currspeed > sysctl_speed_limit_min) {
                         if ((currspeed > sysctl_speed_limit_max) ||
                                         !is_mddev_idle(mddev)) {
-                                msleep(250);
+                                msleep(500);
                                 goto repeat;
                         }
                 }