On Wed, Mar 17, 2010 at 07:31:53PM +0900, KOSAKI Motohiro wrote:
> nit
>
> > +static int compact_zone(struct zone *zone, struct compact_control *cc)
> > +{
> > + int ret = COMPACT_INCOMPLETE;
> > +
> > + /* Setup to move all movable pages to the end of the zone */
> > + cc->migrate_pfn = zone->zone_start_pfn;
> > + cc->free_pfn = cc->migrate_pfn + zone->spanned_pages;
> > + cc->free_pfn &= ~(pageblock_nr_pages-1);
> > +
> > + for (; ret == COMPACT_INCOMPLETE; ret = compact_finished(zone, cc)) {
> > + unsigned long nr_migrate, nr_remaining;
> > + if (!isolate_migratepages(zone, cc))
> > + continue;
> > +
> > + nr_migrate = cc->nr_migratepages;
> > + migrate_pages(&cc->migratepages, compaction_alloc,
> > + (unsigned long)cc, 0);
> > + update_nr_listpages(cc);
> > + nr_remaining = cc->nr_migratepages;
> > +
> > + count_vm_event(COMPACTBLOCKS);
>
> V1 did compaction per pageblock. but current patch doesn't.
> so, Is COMPACTBLOCKS still good name?
>
It's not such a minor nit. I wondered about that myself but it's still a
block - just not a pageblock. Would COMPACTCLUSTER be a better name as it's
related to COMPACT_CLUSTER_MAX?
>
> > + count_vm_events(COMPACTPAGES, nr_migrate - nr_remaining);
> > + if (nr_remaining)
> > + count_vm_events(COMPACTPAGEFAILED, nr_remaining);
> > +
> > + /* Release LRU pages not migrated */
> > + if (!list_empty(&cc->migratepages)) {
> > + putback_lru_pages(&cc->migratepages);
> > + cc->nr_migratepages = 0;
> > + }
> > +
> > + mod_zone_page_state(zone, NR_ISOLATED_ANON, -cc->nr_anon);
> > + mod_zone_page_state(zone, NR_ISOLATED_FILE, -cc->nr_file);
>
> I think you don't need decrease this vmstatistics here. migrate_pages() and
> putback_lru_pages() alredy does.
>
Hmm, I do need to decrease the vmstats here but not by this much. The
pages migrated need to be accounted for but not the ones that failed. I
missed this because migration was always succeeding. Thanks. I'll get it
fixed for V5
> other parts, looks good.
>
--
Mel Gorman
Part-time Phd Student Linux Technology Center
University of Limerick IBM Dublin Software Lab
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxxx For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>