Public issue detail

Runaway CPU investigation for llama-server: unknown userspace loop at uvm_spin_loop

llama-server is stuck in a likely unclassified userspace loop: 23.95% of sampled CPU passed through uvm_spin_loop, with repeated no dominant syscall sample was captured.

highscore: 106reports: 1

Last seen: 2026-10-22 21:36 UTC. Public JSON: /v1/issues/01a0b753-7de3-74d2-bfee-879445fd371b

Technical snapshot

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

Representative thread backtrace

  • Command: /usr/local/lib/ollama/llama-server --list-devices
  • Why Fixer classified it this way: The process is demonstrably CPU-hot, but the current syscall and symbol sample does not point to a single dominant loop family yet.
  • Wait site: 0
  • Hot path: uvm_spin_loop (23.95% sampled CPU)
  • Kernel: 7.1.8+deb14.1-amd64
  • Distribution: debian

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.

cc1 is stuck in a likely unclassified userspace loop: 2.04% of sampled CPU passed through bitmap_set_bit(bitmap_head*, int), with repeated write x88, mmap x1.

highscore: 106reports: 1similarity: 75%

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

Last seen: 2026-10-13 06:02 UTC. Public page: /issues/019fa11d-a82b-79e0-891c-85e9b734e4a0. Public JSON: /v1/issues/019fa11d-a82b-79e0-891c-85e9b734e4a0

lto1 is stuck in a likely unclassified userspace loop: 2.51% of sampled CPU passed through bitmap_set_bit(bitmap_head*, int), with repeated thread backtraces show 1 thread(s) around 0x000000000162a9f7 in constrain_operands(int, unsigned long) ().

highscore: 106reports: 1similarity: 71%

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

Last seen: 2026-09-30 11:46 UTC. Public page: /issues/019fa772-cf3b-7890-82d2-60e7dba39362. Public JSON: /v1/issues/019fa772-cf3b-7890-82d2-60e7dba39362

clang is stuck in a likely unclassified userspace loop: 1.91% of sampled CPU passed through clang::Lexer::LexTokenInternal(clang::Token&, bool), with repeated write x2, close x1, exit_group x1.

highscore: 106reports: 1similarity: 70%

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

Last seen: 2026-10-20 04:50 UTC. Public page: /issues/019ff123-7d66-7253-bc62-d7ba8c5bd3e8. Public JSON: /v1/issues/019ff123-7d66-7253-bc62-d7ba8c5bd3e8

po2xml is stuck in a likely unclassified userspace loop: 53.94% of sampled CPU passed through unresolved offset, with repeated write x2, exit_group x1, fstat x1.

highscore: 106reports: 1similarity: 69%

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

Last seen: 2026-10-19 03:46 UTC. Public page: /issues/01a0f656-df4b-7fc2-acb4-c03fc6235e66. Public JSON: /v1/issues/01a0f656-df4b-7fc2-acb4-c03fc6235e66

Published attempts

No public attempts have been published for this issue yet.