Public issue detail

Runaway CPU investigation for perl: busy poll at update_sd_lb_stats.constprop.0

perl is stuck in a likely busy poll loop: 100.00% of sampled CPU passed through update_sd_lb_stats.constprop.0, with repeated thread backtraces show 1 thread(s) around 0x00007f9a01ce47d2 in ?? () from target:<path>.

highpackage: perl-basesource: perlscore: 106reports: 1

Last seen: 2026-07-04 21:40 UTC. Public JSON: /v1/issues/019f2bc3-ddea-71c0-a8a5-ad543673ae26

Technical snapshot

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

Representative thread backtrace

  • Command: /usr/bin/perl -wT /usr/sbin/munin-node --foreground
  • 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 0x00007f9a01ce47d2 in ?? () from target:<path>
  • Contention signals: gdb-stderr: gdb: warning: Couldn't determine a path for the index cache directory.
  • Repeated loop: pselect6 -> pselect6 -> pselect6
  • Top syscalls: pselect6 x4
  • Package: perl-base 5.40.1-7+b1
  • Kernel: 6.17.10+deb14-amd64
  • Distribution: debian
0x00007f9a01ce47d2 in ?? () from target:<path>
0x000000001502fe47 in ?? ()
0x00005629e3732010 in ?? ()
0x6a3732b173814900 in ?? ()
0x00005629e3c612a0 in ?? ()
0x0000000000000000 in ?? ()

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 perl: busy poll at Perl_runops_standard

possible duplicate

perl is stuck in a likely busy poll loop: 100.00% of sampled CPU passed through Perl_runops_standard, with repeated thread backtraces show 1 thread(s) around 0x00007f704b6f7cb2 in ?? () from target:<path>.

highpackage: perl-basesource: perlscore: 106reports: 3patch attempt readysimilarity: 99%

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

Last seen: 2026-07-10 02:05 UTC. Public page: /issues/019d4017-20f8-7752-9734-0bcd71623118. Public JSON: /v1/issues/019d4017-20f8-7752-9734-0bcd71623118

Runaway CPU investigation for perl: busy poll at native_sched_clock

possible duplicate

perl is stuck in a likely busy poll loop: 100.00% of sampled CPU passed through native_sched_clock, with repeated thread backtraces show 1 thread(s) around 0x00007f5e185decb2 in ?? () from target:<path>.

highpackage: perl-basesource: perlscore: 106reports: 1similarity: 99%

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

Last seen: 2026-07-07 21:30 UTC. Public page: /issues/019f343d-8e8c-7c63-9a54-a9a5e87db750. Public JSON: /v1/issues/019f343d-8e8c-7c63-9a54-a9a5e87db750

Runaway CPU investigation for perl: busy poll at Perl_hv_iternext_flags

possible duplicate

perl is stuck in a likely busy poll loop: 100.00% of sampled CPU passed through Perl_hv_iternext_flags, with repeated thread backtraces show 1 thread(s) around 0x00007f421c5d77d2 in ?? () from target:<path>.

highpackage: perl-basesource: perlscore: 106reports: 1similarity: 99%

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

Last seen: 2026-07-04 05:55 UTC. Public page: /issues/019f1022-894c-7852-a604-32786bebab0d. Public JSON: /v1/issues/019f1022-894c-7852-a604-32786bebab0d

Runaway CPU investigation for perl: busy poll at do_select

possible duplicate

perl is stuck in a likely busy poll loop: 100.00% of sampled CPU passed through do_select, with repeated thread backtraces show 1 thread(s) around 0x00007f4392f987d2 in ?? () from target:<path>.

highpackage: perl-basesource: perlscore: 106reports: 1similarity: 99%

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

Last seen: 2026-06-28 21:10 UTC. Public page: /issues/019db582-c9cc-78d0-8104-f1490ac23dc9. Public JSON: /v1/issues/019db582-c9cc-78d0-8104-f1490ac23dc9

Runaway CPU investigation for python3.13: busy poll at unresolved offset in python3.13

possible duplicate

python3.13 is stuck in a likely busy poll loop: 100.00% of sampled CPU passed through unresolved offset, with repeated thread backtraces show 1 thread(s) around 0x00007f091ce537d2 in ?? () from target:<path>.

highpackage: python3.13-minimalsource: python3.13score: 106reports: 2similarity: 72%

Why this looks related: same classification, same subsystem, same wait site

Last seen: 2026-07-02 03:18 UTC. Public page: /issues/019dc2a0-9ae7-7f42-8f59-415fe22abe51. Public JSON: /v1/issues/019dc2a0-9ae7-7f42-8f59-415fe22abe51

Runaway CPU investigation for rsync: busy poll at clear_page_erms

possible duplicate

rsync is stuck in a likely busy poll loop: 24.28% of sampled CPU passed through clear_page_erms, with repeated thread backtraces show 1 thread(s) around 0x00007f1f5169a7d2 in ?? () from target:<path>.

highpackage: rsyncsource: rsyncscore: 106reports: 2similarity: 71%

Why this looks related: same classification, same subsystem, same wait site

Last seen: 2026-07-02 23:40 UTC. Public page: /issues/019e1a88-12a2-79f0-8a00-0794e663896a. Public JSON: /v1/issues/019e1a88-12a2-79f0-8a00-0794e663896a

Published attempts

No public attempts have been published for this issue yet.

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