502 Error / Unicorn Timeout on Rewind page for highly active users

Bug
1

Hello :waving_hand:

We are experiencing an issue with the Discourse Rewind plugin. For some of our most active users, the Rewind page fails to load and returns a 502 error.

  • The issue seems to be a timeout during the data aggregation process.
  • It consistently happens for users with high activity levels, while working fine for average users.
  • The logs indicate that the Unicorn worker receives a USR2 signal because it exceeds the timeout limit while executing a database query.

Error in console:

Screenshot 2026-01-01 at 14.28.11
Screenshot 2026-01-01 at 14.28.11563×108 11.8 KB

Warning in logs:

Message

Unicorn worker received USR2 signal indicating it is about to timeout, dumping backtrace for main thread
config/unicorn.conf.rb:204:in `backtrace'
config/unicorn.conf.rb:204:in `block (2 levels) in reload'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/rack-mini-profiler-4.0.1/lib/patches/db/pg/alias_method.rb:112:in `exec'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/rack-mini-profiler-4.0.1/lib/patches/db/pg/alias_method.rb:112:in `async_exec'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activerecord-8.0.4/lib/active_record/connection_adapters/postgresql/database_statements.rb:167:in `perform_query'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activerecord-8.0.4/lib/active_record/connection_adapters/abstract/database_statements.rb:556:in `block (2 levels) in raw_execute'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activerecord-8.0.4/lib/active_record/connection_adapters/abstract_adapter.rb:1017:in `block in with_raw_connection'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activesupport-8.0.4/lib/active_support/concurrency/null_lock.rb:9:in `synchronize'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activerecord-8.0.4/lib/active_record/connection_adapters/abstract_adapter.rb:986:in `with_raw_connection'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activerecord-8.0.4/lib/active_record/connection_adapters/abstract/database_statements.rb:555:in `block in raw_execute'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activesupport-8.0.4/lib/active_support/notifications/instrumenter.rb:58:in `instrument'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activerecord-8.0.4/lib/active_record/connection_adapters/abstract_adapter.rb:1137:in `log'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activerecord-8.0.4/lib/active_record/connection_adapters/abstract/database_statements.rb:554:in `raw_execute'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activerecord-8.0.4/lib/active_record/connection_adapters/abstract/database_statements.rb:591:in `...

Backtrace

/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activesupport-8.0.4/lib/active_support/broadcast_logger.rb:218:in `block in dispatch'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activesupport-8.0.4/lib/active_support/broadcast_logger.rb:217:in `map'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activesupport-8.0.4/lib/active_support/broadcast_logger.rb:217:in `dispatch'
/var/www/discourse/vendor/bundle/ruby/3.3.0/gems/activesupport-8.0.4/lib/active_support/broadcast_logger.rb:129:in `warn'
/var/www/discourse/lib/signal_trap_logger.rb:40:in `public_send'
/var/www/discourse/lib/signal_trap_logger.rb:40:in `block (2 levels) in ensure_logging_thread_running'
<internal:kernel>:187:in `loop'
/var/www/discourse/lib/signal_trap_logger.rb:37:in `block in ensure_logging_thread_running'

Thanks

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