Redmine

Hi everyone,
I'm running Redmine in a Kubernetes cluster and experiencing very slow page loads in production.

Environment:
Kubernetes pod resources

Limits:
  cpu: 2
  memory: 4Gi
  ephemeral-storage: 1Gi
Requests:
  cpu: 1
  memory: 2Gi
  ephemeral-storage: 1Gi

Redmine:

Environment:
  Redmine version                6.0.4.stable
  Ruby version                   3.3.7-p123 (2025-01-15) [x86_64-linux]
  Rails version                  7.2.2.1
  Environment                    production
  Database adapter               Mysql2
  Mailer queue                   ActiveJob::QueueAdapters::AsyncAdapter
  Mailer delivery                smtp
Redmine settings:
  Redmine theme                  Default
SCM:
  Subversion                     1.14.2
  Mercurial                      6.3.2
  Bazaar                         3.3.2
  Git                            2.39.5
  Filesystem                     
Redmine plugins:
  approval_process               0.0.3
  imap_authenticate              0.1.0
  recurring_tasks                0.0.1
  redmica_s3                     2.3.1
  redmine_checklists             3.1.24
  redmine_custom_workflows       3.0.0
  redmine_datetime_field         0.0.1
  redmine_omniauth_google        0.0.1
  redmine_slack                  0.2

Puma configuration (puma.rb):

workers 3
threads 8, 32
port 3000
enable_keep_alives(false) if respond_to?(:enable_keep_alives)
rackup DefaultRackup if defined?(DefaultRackup)
environment "production" 

Startup command:

bundle exec puma

Performance issues:

• /activity takes ~1.43 minutes to fully render.
• A single issue page like /issues/11869 takes ~6 seconds.

In logs I see up to 5000 SQL queries during page rendering (many are cached), and over 80 seconds spent in ActiveRecord for some requests. GC and view rendering are fast.

Rendered layout layouts/base.html.erb (Duration: 83748.6ms | GC: 457.0ms)
Completed 200 OK in 85755ms (Views: 4242.4ms | ActiveRecord: 81299.6ms (4965 queries, 3683 cached) | GC: 498.9ms)