From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sat, 11 Feb 2006 14:25:57 -0800 (PST) From: Christoph Lameter Subject: Re: Skip reclaim_mapped determination if we do not swap In-Reply-To: <20060211135031.623fdef9.akpm@osdl.org> Message-ID: References: <20060211135031.623fdef9.akpm@osdl.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: linux-mm@kvack.org, nickpiggin@yahoo.com.au, marcelo.tosatti@cyclades.com List-ID: Here is a new rev of the earlier patch that moves the determination of reclaim_mapped into shrink_zone(). This means that refill_inactive does not depend on scan control anymore. And its properly formatted for 80 columns Signed-off-by: Christoph Lameter Index: linux-2.6.16-rc2/mm/vmscan.c =================================================================== --- linux-2.6.16-rc2.orig/mm/vmscan.c 2006-02-11 13:35:20.000000000 -0800 +++ linux-2.6.16-rc2/mm/vmscan.c 2006-02-11 14:22:07.000000000 -0800 @@ -1168,21 +1168,16 @@ done: * But we had to alter page->flags anyway. */ static void -refill_inactive_zone(struct zone *zone, struct scan_control *sc) +refill_inactive_zone(struct zone *zone, unsigned long nr_pages, int reclaim_mapped) { int pgmoved; int pgdeactivate = 0; int pgscanned; - int nr_pages = sc->nr_to_scan; LIST_HEAD(l_hold); /* The pages which were snipped off */ LIST_HEAD(l_inactive); /* Pages to go onto the inactive_list */ LIST_HEAD(l_active); /* Pages to go onto the active_list */ struct page *page; struct pagevec pvec; - int reclaim_mapped = 0; - long mapped_ratio; - long distress; - long swap_tendency; lru_add_drain(); spin_lock_irq(&zone->lru_lock); @@ -1192,37 +1187,6 @@ refill_inactive_zone(struct zone *zone, zone->nr_active -= pgmoved; spin_unlock_irq(&zone->lru_lock); - /* - * `distress' is a measure of how much trouble we're having reclaiming - * pages. 0 -> no problems. 100 -> great trouble. - */ - distress = 100 >> zone->prev_priority; - - /* - * The point of this algorithm is to decide when to start reclaiming - * mapped memory instead of just pagecache. Work out how much memory - * is mapped. - */ - mapped_ratio = (sc->nr_mapped * 100) / total_memory; - - /* - * Now decide how much we really want to unmap some pages. The mapped - * ratio is downgraded - just because there's a lot of mapped memory - * doesn't necessarily mean that page reclaim isn't succeeding. - * - * The distress ratio is important - we don't want to start going oom. - * - * A 100% value of vm_swappiness overrides this algorithm altogether. - */ - swap_tendency = mapped_ratio / 2 + distress + vm_swappiness; - - /* - * Now use this metric to decide whether to start moving mapped memory - * onto the inactive list. - */ - if (swap_tendency >= 100 && sc->may_swap) - reclaim_mapped = 1; - while (!list_empty(&l_hold)) { cond_resched(); page = lru_to_page(&l_hold); @@ -1304,6 +1268,7 @@ shrink_zone(struct zone *zone, struct sc { unsigned long nr_active; unsigned long nr_inactive; + int reclaim_mapped = 0; atomic_inc(&zone->reclaim_in_progress); @@ -1325,12 +1290,52 @@ shrink_zone(struct zone *zone, struct sc else nr_inactive = 0; + if (sc->may_swap) { + long mapped_ratio; + long distress; + long swap_tendency; + + /* + * `distress' is a measure of how much trouble we're having + * reclaiming pages. 0 -> no problems. 100 -> great trouble. + */ + distress = 100 >> zone->prev_priority; + + /* + * The point of this algorithm is to decide when to start + * reclaiming mapped memory instead of just pagecache. + * Work out how much memory is mapped. + */ + mapped_ratio = (sc->nr_mapped * 100) / total_memory; + + /* + * Now decide how much we really want to unmap some pages. + * The mappe ratio is downgraded - just because there's a lot + * of mapped memory doesn't necessarily mean that page reclaim + * isn't succeeding. + * + * The distress ratio is important - we don't want to start + * going oom. + * + * A 100% value of vm_swappiness overrides this algorithm + * altogether. + */ + swap_tendency = mapped_ratio / 2 + distress + vm_swappiness; + + /* + * Now use this metric to decide whether to start moving + * mapped memory onto the inactive list. + */ + if (swap_tendency >= 100) + reclaim_mapped = 1; + } + while (nr_active || nr_inactive) { if (nr_active) { sc->nr_to_scan = min(nr_active, (unsigned long)sc->swap_cluster_max); nr_active -= sc->nr_to_scan; - refill_inactive_zone(zone, sc); + refill_inactive_zone(zone, sc->nr_to_scan, reclaim_mapped); } if (nr_inactive) { -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org