CGSpace Notes

Documenting day-to-day work on the CGSpace repository.

September, 2024

in  Notes

2024-09-01

  • Upgrade CGSpace to DSpace 7.6.2

2024-09-05

  • Finalize work on migrating DSpace Angular from Yarn to NPM

2024-09-06

  • This morning Tomcat crashed due to an OOM kill:
Sep 06 00:00:24 server systemd[1]: tomcat9.service: A process of this unit has been killed by the OOM killer.
Sep 06 00:00:25 server systemd[1]: tomcat9.service: Main process exited, code=killed, status=9/KILL
Sep 06 00:00:25 server systemd[1]: tomcat9.service: Failed with result 'oom-kill'.
  • According to the system journal, it was a Node.js dspace-angular process that tried to allocate memory and failed, thus invoking the OOM killer
  • Currently I see high memory usage in those processes:
$ pm2 status
┌────┬──────────────┬─────────────┬─────────┬─────────┬──────────┬────────┬──────┬───────────┬──────────┬──────────┬──────────┬──────────┐
│ id │ name         │ namespace   │ version │ mode    │ pid      │ uptime │ ↺    │ status    │ cpu      │ mem      │ user     │ watching │
├────┼──────────────┼─────────────┼─────────┼─────────┼──────────┼────────┼──────┼───────────┼──────────┼──────────┼──────────┼──────────┤
│ 0  │ dspace-ui    │ default     │ 7.6.3-… │ cluster │ 994      │ 4D     │ 0    │ online    │ 0%       │ 3.4gb    │ dspace   │ disabled │
│ 1  │ dspace-ui    │ default     │ 7.6.3-… │ cluster │ 1015     │ 4D     │ 0    │ online    │ 0%       │ 3.4gb    │ dspace   │ disabled │
│ 2  │ dspace-ui    │ default     │ 7.6.3-… │ cluster │ 1029     │ 4D     │ 0    │ online    │ 0%       │ 3.4gb    │ dspace   │ disabled │
│ 3  │ dspace-ui    │ default     │ 7.6.3-… │ cluster │ 1042     │ 4D     │ 0    │ online    │ 0%       │ 3.4gb    │ dspace   │ disabled │
└────┴──────────────┴─────────────┴─────────┴─────────┴──────────┴────────┴──────┴───────────┴──────────┴──────────┴──────────┴──────────┘
  • I bet if I look in the logs I’d find some kind of heavy traffic on the frontend, causing high caching for Angular SSR

2024-09-08

  • Analyzing memory use in our DSpace hosts, which have 32GB of memory
    • Effective cache of PostgreSQL is estimated at 11GB, which seems way high since the database is only 2GB
    • Realistically this should be how we adjust, with PostgreSQL using ~8GB (or less) and each dspace-angular process pinned at 2GB…

Total - Solr - Tomcat Postgres - Nginx - Angular 31366 − (1024×4.4) − 7168 − (8×1024) − 512 - (4x2048) = 2796.4 left…

  • I put some of these changes in on DSpace Test and will monitor this week