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Live lock in acquire_spin_lock_slow_path

Summary

My program is sometime stuck, tacking CPU (100% of one capability), and making no progress.

When using perf top, I can observe that all the time is spent in acquire_spin_lock_slow_path, see image

Steps to reproduce

Unfortunately, I cannot reproduce easilly. What I know is:

  • I'm using GHC 9.2.1
  • This program is complex, involve multi threading, using -N8
  • The program uses weak reference finalizers

Expected behavior

My program should not live lock?

Environment

  • GHC version used: 9.2.1

Optional:

  • Operating System: Linux
  • System Architecture: x86_64

I found this log $2047 posted by @bgamari which may be related, but no ticket associated. At least, if the problem is already known / fixed, this ticket will be an entrypoint for reference.

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