Hi Sage, On Tue, May 10, 2011 at 6:02 PM, Sage Weil <sage@xxxxxxxxxxxx> wrote: > Hi Stefan, > > On Tue, 10 May 2011, Stefan Majer wrote: >> Hi, >> >> On Tue, May 10, 2011 at 4:20 PM, Yehuda Sadeh Weinraub >> <yehudasa@xxxxxxxxx> wrote: >> > On Tue, May 10, 2011 at 7:04 AM, Stefan Majer <stefan.majer@xxxxxxxxx> wrote: >> >> Hi, >> >> >> >> im running 4 nodes with ceph on top of btrfs with a dualport Intel >> >> X520 10Gb Ethernet Card with the latest 3.3.9 ixgbe driver. >> >> during benchmarks i get the following stack. >> >> I can easily reproduce this by simply running rados bench from a fast >> >> machine using this 4 nodes as ceph cluster. >> >> We saw this with stock ixgbe driver from 2.6.38.6 and with the latest >> >> 3.3.9 ixgbe. >> >> This kernel is tainted because we use fusion-io iodrives as journal >> >> devices for btrfs. >> >> >> >> Any hints to nail this down are welcome. >> >> >> >> Greetings Stefan Majer >> >> >> >> May 10 15:26:40 os02 kernel: [ 3652.485219] cosd: page allocation >> >> failure. order:2, mode:0x4020 >> > >> > It looks like the machine running the cosd is crashing, is that the case? >> >> No the machine is still running. Even the cosd is still there. > > How much memory is (was?) cosd using? Is it possible for you to watch RSS > under load when the errors trigger? I will look on this tomorrow just for the record: each machine has 24GB of RAM and 4 cosd with 1 btrfs formated disks each, which is a raid5 over 3 2TB spindles. The rados bench reaches a constant rate of about 1000Mb/sec ! Greetings Stefan > The osd throttles incoming client bandwidth, but it doesn't throttle > inter-osd traffic yet because it's not obvious how to avoid deadlock. > It's possible that one node is getting significantly behind the > others on the replicated writes and that is blowing up its memory > footprint. There are a few ways we can address that, but I'd like to make > sure we understand the problem first. > > Thanks! > sage > > > >> > Are you running both ceph kernel module on the same machine by any >> > chance? If not, it can be some other fs bug (e.g., the underlying >> > btrfs). Also, the stack here is quite deep, there's a chance for a >> > stack overflow. >> >> There is only the cosd running on these machines. We have 3 seperate >> mons and clients which uses qemu-rbd. >> >> >> > Thanks, >> > Yehuda >> > >> >> >> Greetings >> -- >> Stefan Majer >> -- >> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >> > -- Stefan Majer -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
