On Fri, 10 Feb 2012, Jeff Moyer wrote: > Sage Weil <sage@xxxxxxxxxxxx> writes: > > > I hit the following under a reasonable simple aio workload: > > > > - reasonably heavy load > > - lots of threads doing buffered io to random files > > - one thread submitting O_DIRECT aio to a single file (journal), all > > sequential (wrapping), 100MB > > - probably somewhere between 1 and 50 aios outstanding at any point in > > time. > > > > The kernel was v3.2 mainline, plus unrelated btrfs and ceph patches. > > > > Is this a known issue? Any other information that would be helpful? > > I don't know for sure, but could you test with the following commit? > 69e4747ee9727d660b88d7e1efe0f4afcb35db1b I'll pull this in and see if it comes up again (this is the first time I've seen the crash). > Also, I'll note that it looks like you are doing O_SYNC + O_DIRECT AIO. > I'm curious to know what apps use that particular combination. Is this > just a test case, or do you have an app which does this in production? That's what ceph-osd is doing on it's journal. Rereading the man page it's not clear to me what I *should* be doing, though. Would you use O_SYNC (with O_DIRECT) only to make sure the blocks you write to are allocated/reachable on crash? (Or, say, mtime is updated?) sage -- 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
