On Tuesday January 15, akpm@xxxxxxxxxxxxxxxxxxxx wrote: > On Wed, 16 Jan 2008 00:09:31 -0700 "Dan Williams" <dan.j.williams@xxxxxxxxx> wrote: > > > > heheh. > > > > > > it's really easy to reproduce the hang without the patch -- i could > > > hang the box in under 20 min on 2.6.22+ w/XFS and raid5 on 7x750GB. > > > i'll try with ext3... Dan's experiences suggest it won't happen with ext3 > > > (or is even more rare), which would explain why this has is overall a > > > rare problem. > > > > > > > Hmmm... how rare? > > > > http://marc.info/?l=linux-kernel&m=119461747005776&w=2 > > > > There is nothing specific that prevents other filesystems from hitting > > it, perhaps XFS is just better at submitting large i/o's. -stable > > should get some kind of treatment. I'll take altered performance over > > a hung system. > > We can always target 2.6.25-rc1 then 2.6.24.1 if Neil is still feeling > wimpy. I am feeling wimpy. There've been a few too many raid5 breakages recently and it is very hard to really judge the performance impact of this change. I even have a small uncertainty of correctness - could it still hang in some other way? I don't think so, but this is complex code... If it were really common I would have expected more noise on the mailing list. Sure, there has been some, but not much. However maybe people are searching the archives and finding the "increase stripe cache size" trick, and not reporting anything .... seems unlikely though. How about we queue it for 2.6.25-rc1 and then about when -rc2 comes out, we queue it for 2.6.24.y? Any one (or any distro) that really needs it can of course grab the patch them selves... ?? NeilBrown - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
