https://github.com/dun/munge/issues/94
The NEWS file claims this was fixed in 0.5.15. Since your log doesn't show the additional strerror() output you're definitely running an older version, correct? If you go on one of the affected nodes and do an `lsof -p <munged-pid>` I'm betting you'll find a long list of open file descriptors — that would explain the "Too many open files" situation _and_ indicate that this is something other than external memory pressure or open file limits on the process. > On Apr 15, 2024, at 08:14, Ole Holm Nielsen via slurm-users > <slurm-users@lists.schedmd.com> wrote: > > We have some new AMD EPYC compute nodes with 96 cores/node running RockyLinux > 8.9. We've had a number of incidents where the Munge log-file > /var/log/munge/munged.log suddenly fills up the root file system, after a > while to 100% (tens of GBs), and the node eventually comes to a grinding > halt! Wiping munged.log and restarting the node works around the issue. > > I've tried to track down the symptoms and this is what I found: > > 1. In munged.log there are infinitely many lines filling up the disk: > > 2024-04-11 09:59:29 +0200 Info: Suspended new connections while > processing backlog > > 2. The slurmd is not getting any responses from munged, even though we run > "munged --num-threads 10". The slurmd.log displays errors like: > > [2024-04-12T02:05:45.001] error: If munged is up, restart with > --num-threads=10 > [2024-04-12T02:05:45.001] error: Munge encode failed: Failed to connect to > "/var/run/munge/munge.socket.2": Resource temporarily unavailable > [2024-04-12T02:05:45.001] error: slurm_buffers_pack_msg: auth_g_create: > RESPONSE_ACCT_GATHER_UPDATE has authentication error > > 3. The /var/log/messages displays the errors from slurmd as well as > NetworkManager saying "Too many open files in system". > The telltale syslog entry seems to be: > > Apr 12 02:05:48 e009 kernel: VFS: file-max limit 65536 reached > > where the limit is confirmed in /proc/sys/fs/file-max. > > We have never before seen any such errors from Munge. The error may perhaps > be triggered by certain user codes (possibly star-ccm+) that might be opening > a lot more files on the 96-core nodes than on nodes with a lower core count. > > My workaround has been to edit the line in /etc/sysctl.conf: > > fs.file-max = 131072 > > and update settings by "sysctl -p". We haven't seen any of the Munge errors > since! > > The version of Munge in RockyLinux 8.9 is 0.5.13, but there is a newer > version in https://github.com/dun/munge/releases/tag/munge-0.5.16 > I can't figure out if 0.5.16 has a fix for the issue seen here? > > Questions: Have other sites seen the present Munge issue as well? Are there > any good recommendations for setting the fs.file-max parameter on Slurm > compute nodes? > > Thanks for sharing your insights, > Ole > > -- > Ole Holm Nielsen > PhD, Senior HPC Officer > Department of Physics, Technical University of Denmark > > -- > slurm-users mailing list -- slurm-users@lists.schedmd.com > To unsubscribe send an email to slurm-users-le...@lists.schedmd.com -- slurm-users mailing list -- slurm-users@lists.schedmd.com To unsubscribe send an email to slurm-users-le...@lists.schedmd.com
