From e9299f5058595a655c3b207cda9635e28b9197e6 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Fri, 8 Jul 2011 14:14:37 +1000 Subject: vmscan: add customisable shrinker batch size For shrinkers that have their own cond_resched* calls, having shrink_slab break the work down into small batches is not paticularly efficient. Add a custom batchsize field to the struct shrinker so that shrinkers can use a larger batch size if they desire. A value of zero (uninitialised) means "use the default", so behaviour is unchanged by this patch. Signed-off-by: Dave Chinner Signed-off-by: Al Viro --- mm/vmscan.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'mm') diff --git a/mm/vmscan.c b/mm/vmscan.c index 387422470c95..febbc044e792 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -253,6 +253,8 @@ unsigned long shrink_slab(struct shrink_control *shrink, int shrink_ret = 0; long nr; long new_nr; + long batch_size = shrinker->batch ? shrinker->batch + : SHRINK_BATCH; /* * copy the current shrinker scan count into a local variable @@ -303,19 +305,18 @@ unsigned long shrink_slab(struct shrink_control *shrink, nr_pages_scanned, lru_pages, max_pass, delta, total_scan); - while (total_scan >= SHRINK_BATCH) { - long this_scan = SHRINK_BATCH; + while (total_scan >= batch_size) { int nr_before; nr_before = do_shrinker_shrink(shrinker, shrink, 0); shrink_ret = do_shrinker_shrink(shrinker, shrink, - this_scan); + batch_size); if (shrink_ret == -1) break; if (shrink_ret < nr_before) ret += nr_before - shrink_ret; - count_vm_events(SLABS_SCANNED, this_scan); - total_scan -= this_scan; + count_vm_events(SLABS_SCANNED, batch_size); + total_scan -= batch_size; cond_resched(); } -- cgit v1.2.3