On Fri, Dec 14, 2012 at 06:06:50PM -0800, Andy Lutomirski wrote: > On Fri, Dec 14, 2012 at 6:01 PM, Darrick J. Wong > <darrick.wong@xxxxxxxxxx> wrote: > > On Fri, Dec 14, 2012 at 05:12:37PM -0800, Andy Lutomirski wrote: > >> It survived. I hit at least one mm bug, but I really don't think it's > >> a problem with your code. (I have not tried this workload on Linux > >> 3.7 at all before. It normally runs on 3.5.) The box in question is > > > > Would you mind sending along the bug report so I can make sure? > > http://marc.info/?l=linux-mm&m=135553342803210&w=2 Hm, this looks like a hugepages thing, which (afaik) doesn't touch fs code at all. Looks like this patchset is in the clear. > > > >> ext4 on LVM on dm-crypt on (hardware) RAID 5 on hpsa, which should not > >> need stable pages. > >> > >> The majority of the data written (that wasn't unlinked before it was > >> dropped from cache) was checksummed when written and verified later. > >> Most of this data was written using mmap. This workload hammers the > >> vm concurrently in several threads, and it frequently stalls when > >> stable pages are enabled, so it's probably exercising the code > >> decently well. > > > > Did you observe any change in performance? > > No. But I'm comparing to 3.5 + butchery to remove stable pages. With > stable pages on, this workload performs terribly. (It's a soft > real-time thing, as you can possibly guess from my domain name, and > various latency monitoring things go nuts when stable pages are > active.) Well, I guess that's good. :) > Actually, performance appears to be improved, probably due to > https://lkml.org/lkml/2012/12/14/14, which I tested concurrently. > > > > >> Feel free to add Tested-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx> > > > > Will do! Thanks for the testing! > > My pleasure. When these changes go in to an upstream kernel, they'll > represent a significant reduction in how much our kernel differs from > kernel.org's :) Thanks for fixing this. No problem! --D -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
