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Guide

Mar 19, 2020

Solved

After OOM kills, Readynas doesn't restart killed services

Hi All,

I understand that I'm running out of memory and the system is doing its best to recover by killing processes via OOM. But why doesn't the OS restart those services afterwards? If SMB goes down, it stays down --- if the web service goes down, it stays down. Would there be harm in updating the systemd service defintions to restart on failure? Currently they are written like so (smb.conf):

cat /lib/systemd/system/smb.service
[Unit]
Description=Samba SMB Daemon
After=syslog.target network.target avahi-daemon.service nmb.service winbind.service
Wants=wsdd2.service

[Service]
Type=notify
NotifyAccess=all
PIDFile=/run/smbd.pid
LimitNOFILE=16384
EnvironmentFile=-/etc/sysconfig/samba
EnvironmentFile=-/etc/default/tracker
ExecStart=/usr/sbin/smbd --foreground --no-process-group $SMBDOPTIONS
ExecReload=/bin/kill -HUP $MAINPID

[Install]
WantedBy=multi-user.target

Is there some other mechanism in OS6 that should be restarting services if they crash or are killed by the system?

If I updated the services of things like Readynas and smb - would that fix my problem if/when these are killed via OOM?

PS: I'm installing more memory to the system today to go from 1GB to 4GB, but still wanted to ask why the system doesn't recover after these OOM processes take effect... Basically the system cascades down if OOMs happen.

Thanks

jrover
Mar 23, 2020
The additional memory looks to have stabilized my ReadyNAS Ultra 6 Plus. Running at 1GB seemed to make the machine unstable on OS6. With 4GB, the box appears stable with services/etc (non-caching) using ~400MB on v6.10.3, running SMB,Rsync,HTTP/S,SNMP,SSH. I'll keep looking for OOM kills, but likely the $17 of memory was worth it :)

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jrover
Guide
Mar 23, 2020
The additional memory looks to have stabilized my ReadyNAS Ultra 6 Plus. Running at 1GB seemed to make the machine unstable on OS6. With 4GB, the box appears stable with services/etc (non-caching) using ~400MB on v6.10.3, running SMB,Rsync,HTTP/S,SNMP,SSH. I'll keep looking for OOM kills, but likely the $17 of memory was worth it :)
- Sandshark
  Sensei - Experienced User
  Mar 23, 2020
  Since all current OS6 models have at least 2GB of RAM, it has long been recommended that a user migrating a legacy NAS to OS6 follow suit. It looks like that may need to be more than a recommendation from this point forward, likely due to size increases in the OS itself.
  - StephenB
    Guru - Experienced User
    Mar 24, 2020
    Sandshark wrote:
    
    Since all current OS6 models have at least 2GB of RAM, it has long been recommended that a user migrating a legacy NAS to OS6 follow suit. It looks like that may need to be more than a recommendation from this point forward, likely due to size increases in the OS itself.
    
    Yes, I agree it should be more than a suggestion (which is how I've phrased it in the past).