Public issue detail

Runaway CPU investigation for postgres: busy poll at __dquot_initialize

postgres is stuck in a likely busy poll loop: 50.00% of sampled CPU passed through __dquot_initialize, with repeated thread backtraces show 1 thread(s) around 0x00007f322d29a7d2 in ?? () from target:<path>.

highpackage: postgresql-18source: postgresql-18score: 106reports: 1

Last seen: 2026-06-06 05:55 UTC. Public JSON: /v1/issues/019e9b4c-f6e3-70a0-9d44-9ac4a74629e4

Technical snapshot

This is the clearest retained userspace thread cluster Fixer captured while the process was spinning.

Representative thread backtrace

  • Command: /usr/lib/postgresql/18/bin/postgres -D /var/lib/postgresql/18/main -c config_file=/etc/postgresql/18/main/postgresql.conf
  • Why Fixer classified it this way: The trace repeatedly returns to a poll-family syscall without meaningful blocking, which suggests a busy event-loop wakeup.
  • Thread summary: thread backtraces show 1 thread(s) around 0x00007f322d29a7d2 in ?? () from target:<path>
  • Contention signals: event-loop-wakeups, gdb-stderr: gdb: warning: Couldn't determine a path for the index cache directory. warning: .dynamic section for "target:<path>++.so.6" is not at the expected address (wrong library or version mismatch?)
  • Repeated loop: epoll_wait
  • Top syscalls: epoll_wait x1
  • Package: postgresql-18 18.3-1.pgdg+2
  • Kernel: 6.17.10+deb14-amd64
  • Distribution: debian
0x00007f322d29a7d2 in ?? () from target:<path>
0x00007f322d29a7ed in ?? () from target:<path>
0x00007f322d31d0cd in epoll_wait () from target:<path>
0x00005574dfc994fa in WaitEventSetWait ()
0x00005574dfc02498 in ?? ()
0x00005574dfc04e45 in PostmasterMain ()
0x00005574df8a335a in main ()

Possible duplicates

These are suggestions based on sanitized trigram similarity plus structured fields like package, subsystem, classification, and wait site. They are not auto-merged.

Runaway CPU investigation for postgres: busy poll at __list_del_entry_valid_or_report

possible duplicate

postgres is stuck in a likely busy poll loop: 9.52% of sampled CPU passed through __list_del_entry_valid_or_report, with repeated thread backtraces show 1 thread(s) around 0x00007f322d29a7d2 in ?? () from target:<path>.

highpackage: postgresql-18source: postgresql-18score: 106reports: 2similarity: 99%

Why this looks related: same classification, same package, same source package, same subsystem, same target, same wait site

Last seen: 2026-06-10 02:24 UTC. Public page: /issues/019dbb32-2e8b-7290-81ab-fe0fc2a39939. Public JSON: /v1/issues/019dbb32-2e8b-7290-81ab-fe0fc2a39939

Runaway CPU investigation for postgres: busy poll at lock_vma_under_rcu

possible duplicate

postgres is stuck in a likely busy poll loop: 7.53% of sampled CPU passed through lock_vma_under_rcu, with repeated thread backtraces show 1 thread(s) around 0x00007f322d29a7d2 in ?? () from target:<path>.

highpackage: postgresql-18source: postgresql-18score: 106reports: 2similarity: 99%

Why this looks related: same classification, same package, same source package, same subsystem, same target, same wait site, very similar public summary

Last seen: 2026-06-10 01:27 UTC. Public page: /issues/019da9d3-d031-76f1-a9a6-28d68812045c. Public JSON: /v1/issues/019da9d3-d031-76f1-a9a6-28d68812045c

Runaway CPU investigation for postgres: busy poll at next_uptodate_folio

possible duplicate

postgres is stuck in a likely busy poll loop: 16.28% of sampled CPU passed through next_uptodate_folio, with repeated thread backtraces show 1 thread(s) around 0x00007f322d29a7d2 in ?? () from target:<path>.

highpackage: postgresql-18source: postgresql-18score: 106reports: 2successful triagesimilarity: 99%

Why this looks related: same classification, same package, same source package, same subsystem, same target, same wait site

Last seen: 2026-06-10 00:32 UTC. Public page: /issues/019dd9b3-4d4e-73f0-86bb-bf7e642a5785. Public JSON: /v1/issues/019dd9b3-4d4e-73f0-86bb-bf7e642a5785

Runaway CPU investigation for postgres: busy poll at clear_page_erms

possible duplicate

postgres is stuck in a likely busy poll loop: 18.80% of sampled CPU passed through clear_page_erms, with repeated thread backtraces show 1 thread(s) around 0x00007f322d29a7d2 in ?? () from target:<path>.

highpackage: postgresql-18source: postgresql-18score: 106reports: 2successful triagesimilarity: 99%

Why this looks related: same classification, same package, same source package, same subsystem, same target, same wait site, very similar public summary

Last seen: 2026-06-09 23:18 UTC. Public page: /issues/019dd8ad-5fbe-71e3-bb82-e8e5eca88dd0. Public JSON: /v1/issues/019dd8ad-5fbe-71e3-bb82-e8e5eca88dd0

Runaway CPU investigation for postgres: busy poll at filemap_map_pages

possible duplicate

postgres is stuck in a likely busy poll loop: 12.80% of sampled CPU passed through filemap_map_pages, with repeated thread backtraces show 1 thread(s) around 0x00007f322d29a7d2 in ?? () from target:<path>.

highpackage: postgresql-18source: postgresql-18score: 106reports: 2successful triagesimilarity: 99%

Why this looks related: same classification, same package, same source package, same subsystem, same target, same wait site, very similar public summary

Last seen: 2026-06-09 05:43 UTC. Public page: /issues/019dda03-7a7e-7fd1-bf01-105bf190069d. Public JSON: /v1/issues/019dda03-7a7e-7fd1-bf01-105bf190069d

Runaway CPU investigation for postgres: busy poll at __handle_mm_fault

possible duplicate

postgres is stuck in a likely busy poll loop: 8.34% of sampled CPU passed through __handle_mm_fault, with repeated thread backtraces show 1 thread(s) around 0x00007f322d29a7d2 in ?? () from target:<path>.

highpackage: postgresql-18source: postgresql-18score: 106reports: 2successful triagesimilarity: 99%

Why this looks related: same classification, same package, same source package, same subsystem, same target, same wait site, very similar public summary

Last seen: 2026-06-09 03:13 UTC. Public page: /issues/019db073-8716-7230-93d8-bfa9391f8501. Public JSON: /v1/issues/019db073-8716-7230-93d8-bfa9391f8501

Published attempts

No public attempts have been published for this issue yet.

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