Okay so one thing I noticed on both instances is that there was a Metadata server outage a few days before the users complained about these issues. The clients reestablished the connection once the metadata services were brought back online. But my understanding was that the processes would just hang while the storage is unavailable. But it should be fine once the lustre filesystem was made available again. Am I incorrect in this assumption? Could this have led to these processes being in this hung state? Again, it does not seem like all processes across all nodes were effected.<br>
<br>Thanks,<br>-Simran<br><br><div class="gmail_quote">On Wed, Oct 13, 2010 at 2:33 PM, Jagga Soorma <span dir="ltr"><<a href="mailto:jagga13@gmail.com">jagga13@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
Hey Guys,<br><br>I have 16 clients running lustre 1.8.1.1 and 8 new clients running 1.8.4. My server is still running lustre 1.8.1.1 (RHEL 5.3). I just deployed these new nodes a few weeks ago and have started seeing some user processes just go into an uninteruptable state. When this same workload is performed on the 1.8.1.1 clients it runs fine, but when we run it in our 1.8.4 clients we start seeing this issue. All my clients are setup with SLES11 and the same packages with the exception of a newer kernel in the 1.8.4 environment due to the lustre dependency:<br>
<br>reshpc208:~ # uname -a<br>Linux reshpc208 2.6.27.39-0.3-default #1 SMP 2009-11-23 12:57:38 +0100 x86_64 x86_64 x86_64 GNU/Linux<br>reshpc208:~ # rpm -qa | grep -i lustre<br>lustre-client-modules-1.8.4-2.6.27_39_0.3_lustre.1.8.4_default<br>
lustre-client-1.8.4-2.6.27_39_0.3_lustre.1.8.4_default<br>reshpc208:~ # rpm -qa | grep -i kernel-ib<br>kernel-ib-1.5.1-2.6.27.39_0.3_default<br><br>Doing a ps just hangs on the system and I need to just close and reopen a session to the effected system. The application (gsnap) is running from the lustre filesystem and doing all IO to the lustre fs. Here is a strace of where ps hangs:<br>
<br>--<br>output from "strace ps -ef"<br><br>doing an ls in /proc/9598 just hangs the session as well<br><br>..snip..<br>open("/proc/9597/cmdline", O_RDONLY) = 6<br>read(6, "sh\0-c\0/gne/home/coryba/bin/gsnap"..., 2047) = 359<br>
close(6) = 0<br>stat("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2819, ...}) = 0<br>stat("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2819, ...}) = 0<br>write(1, "degenhj2 9597 9595 0 11:35 ? "..., 130degenhj2 9597 9595 0 11:35 ? 00:00:00 sh -c /gne/home/coryba/bin/gsnap -M 3 -t 16 -m 3 -n 1 -d mm9 -e 1000 -E 1000 --pa<br>
) = 130<br>stat("/proc/9598", {st_mode=S_IFDIR|0555, st_size=0, ...}) = 0<br>open("/proc/9598/stat", O_RDONLY) = 6<br>read(6, "9598 (gsnap) S 9596 9589 9589 0 "..., 1023) = 254<br>close(6) = 0<br>
open("/proc/9598/status", O_RDONLY) = 6<br>read(6, "Name:\tgsnap\nState:\tS (sleeping)\n"..., 1023) = 1023<br>close(6) = 0<br>open("/proc/9598/cmdline", O_RDONLY) = 6<br>
read(6, <br>--<br><br>The "t" before "gsnap" is part of "\t", or a "tab" character. It looks like GSNAP was trying to open a file or read from it.<br><br>I don't see any recent lustre specific errors in my logs (The ones from Oct 10th are expected):<br>
<br>--<br>..snip..<br>Oct 10 12:52:01 reshpc208 kernel: Lustre: 12933:0:(import.c:517:import_select_connection()) reshpcfs-MDT0000-mdc-ffff88200d5d2400: tried all connections, increasing latency to 2s<br>Oct 10 12:52:01 reshpc208 kernel: Lustre: 12933:0:(import.c:517:import_select_connection()) Skipped 2 previous similar messages<br>
Oct 10 12:52:29 reshpc208 kernel: LustreError: 166-1: MGC10.0.250.44@o2ib3: Connection to service MGS via nid 10.0.250.44@o2ib3 was lost; in progress operations using this service will fail.<br>Oct 10 12:52:43 reshpc208 kernel: Lustre: 12932:0:(import.c:855:ptlrpc_connect_interpret()) <a href="mailto:MGS@10.0.250.44" target="_blank">MGS@10.0.250.44</a>@o2ib3 changed server handle from 0x816b8508159f149f to 0x816b850815ae68ab<br>
Oct 10 12:52:43 reshpc208 kernel: Lustre: MGC10.0.250.44@o2ib3: Reactivating import<br>Oct 10 12:52:43 reshpc208 kernel: Lustre: MGC10.0.250.44@o2ib3: Connection restored to service MGS using nid 10.0.250.44@o2ib3.<br>Oct 10 12:52:43 reshpc208 kernel: Lustre: Skipped 1 previous similar message<br>
Oct 10 12:52:45 reshpc208 kernel: LustreError: 11-0: an error occurred while communicating with 10.0.250.44@o2ib3. The obd_ping operation failed with -107<br>--<br><br>Again we don't have any issues on our 1.8.1.1 client's and this seems to be only happening on our 1.8.4 clients. Any assistance would be greatly appreciated.<br>
<br>Has anyone seen anything similar to this? Should I just revert back to 1.8.1.1 on these new nodes? When is 1.8.5 supposed to come out? I would prefer to jump to SLES 11 SP1.<br><br>Thanks,<br><font color="#888888">-J<br>
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