On Sun, 3 Jun 2012, Dave Jones wrote: > On Sun, Jun 03, 2012 at 02:31:39PM -0400, Dave Jones wrote: > > On Sun, Jun 03, 2012 at 11:23:29AM -0700, Linus Torvalds wrote: > > > On Sun, Jun 3, 2012 at 11:15 AM, Dave Jones <davej@xxxxxxxxxx> wrote: > > > > > > > > Things aren't happy with that patch at all. > > > > > > Yeah, at this point I think we need to just revert the compaction changes. > > > > > > Guys, what's the minimal set of commits to revert? That clearly buggy > > > "rescue_unmovable_pageblock()" function was introduced by commit > > > 5ceb9ce6fe94, but is that actually involved with the particular bug? > > > That commit seems to revert cleanly still, but is that sufficient or > > > does it even matter? > > > > I'l rerun the test with that (and Hugh's last patch) backed out, and see > > if that makes any difference. > > running just over two hours with that commit reverted with no obvious ill effects so far. Yes, and I ran happily with precisely that commit reverted on Friday - though I've never got the list corruption that you saw with it in. The locking bug certainly comes in with that commit, it's an isolated commit that reverts cleanly, and I think you got the list corruption rather sooner than two hours before (9min, 30min, 41min from the traces you sent). Maybe we should let you run a little longer, or wait for others to comment. But another strike against that commit: I tried fixing it up to use start_page instead of page at the end, with the worrying but safer locking I suggested at first, with a count of how many times it went there, and how many times it succeeded. While I ran my usual swapping test (perhaps that's a very unfair test to run on this, I've no idea) for seven hours, it went there 25406 times (once per second, it appears) and it succeeded... 0 times. Let's hope it failed quickly each time, I wasn't capturing that. Hugh -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>