Public issue detail

Runaway CPU investigation for ollama: unknown userspace loop at unresolved offset in ollama

ollama is stuck in a likely unclassified userspace loop: 12.27% of sampled CPU passed through unresolved offset, with repeated thread backtraces show 1 thread(s) around 0x000055c5c39ed143 in ?? () and 1 thread(s) around 0x000055c5c39ed143 in ?? ().

highscore: 106reports: 3successful triage

Last seen: 2026-07-10 03:06 UTC. Public JSON: /v1/issues/019dd7a7-430c-79a0-bc5b-7549a044b3fc

Successful triage

Fixer did not find an honest diff-backed change in this source tree. Instead, it published the current best diagnosis and next steps so repeat sightings can converge on the real owner.

best triagecreated: 2026-05-27 05:09 UTCvalidation: ready

ollama likely remains stuck in an unclassified userspace loop. A diagnosis report and external handoff were created locally.

Likely owner

local executable ollama

Reason: workspace-acquisition

Suggested bug target: https://github.com/ollama/ollama.git

Next steps

  • Use the source repository identified from the executable metadata (https://github.com/ollama/ollama.git) before asking Fixer for a patch.
  • Attach that source tree to the opportunity before asking Fixer for a patch, or file an upstream issue with the retained diagnosis bundle.
  • Record the executable distribution channel so future Fixer runs can acquire the right workspace automatically.

Technical snapshot

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

Representative thread backtrace

  • Command: /usr/local/bin/ollama serve
  • 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.
  • Thread summary: thread backtraces show 1 thread(s) around 0x000055c5c39ed143 in ?? () and 1 thread(s) around 0x000055c5c39ed143 in ?? ()
  • Contention signals: 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: futex -> futex -> futex
  • Top syscalls: futex x52, epoll_pwait x1, restart_syscall x1
  • Kernel: 6.17.10+deb14-amd64
  • Distribution: debian
0x000055c5c39ed143 in ?? ()
0x000055c5c39a9110 in ?? ()
0x000000c000581148 in ?? ()
0x0000000000000080 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.

ollama is stuck in a likely unclassified userspace loop: 12.32% of sampled CPU passed through unresolved offset, with repeated thread backtraces show 1 thread(s) around 0x000055c5c39ed143 in ?? () and 1 thread(s) around 0x000055c5c39ed143 in ?? ().

highscore: 106reports: 2successful triagesimilarity: 99%

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

Last seen: 2026-07-07 10:52 UTC. Public page: /issues/019dd37a-eda1-7411-9089-0f3b6dd792aa. Public JSON: /v1/issues/019dd37a-eda1-7411-9089-0f3b6dd792aa

ollama is stuck in a likely unclassified userspace loop: 25.00% of sampled CPU passed through __free_one_page, with repeated thread backtraces show 1 thread(s) around 0x000055c5c39ed143 in ?? () and 1 thread(s) around 0x000055c5c39ed143 in ?? ().

highscore: 106reports: 1successful triagesimilarity: 99%

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

Last seen: 2026-07-07 21:30 UTC. Public page: /issues/019dba91-e079-7393-8193-774ba6aa0b53. Public JSON: /v1/issues/019dba91-e079-7393-8193-774ba6aa0b53

ollama is stuck in a likely unclassified userspace loop: 25.00% of sampled CPU passed through _raw_spin_lock_irqsave, with repeated thread backtraces show 1 thread(s) around 0x000055c5c39ed143 in ?? () and 1 thread(s) around 0x000055c5c39ed143 in ?? ().

highscore: 106reports: 1successful triagesimilarity: 99%

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

Last seen: 2026-07-07 19:59 UTC. Public page: /issues/019d780b-a338-7841-9ba2-3bf6ad9294de. Public JSON: /v1/issues/019d780b-a338-7841-9ba2-3bf6ad9294de

ollama is stuck in a likely unclassified userspace loop: 33.33% of sampled CPU passed through fdget, with repeated thread backtraces show 1 thread(s) around 0x000055c5c39ed143 in ?? () and 1 thread(s) around 0x000055c5c39ed143 in ?? ().

highscore: 106reports: 1successful triagesimilarity: 99%

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

Last seen: 2026-07-07 14:12 UTC. Public page: /issues/019dbcec-f056-7ae0-bc8f-d6d03bb07fcc. Public JSON: /v1/issues/019dbcec-f056-7ae0-bc8f-d6d03bb07fcc

ollama is stuck in a likely unclassified userspace loop: 26.50% of sampled CPU passed through fput, with repeated thread backtraces show 1 thread(s) around 0x000055c5c39ed143 in ?? () and 1 thread(s) around 0x000055c5c39ed143 in ?? ().

highscore: 106reports: 1successful triagesimilarity: 99%

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

Last seen: 2026-07-06 09:10 UTC. Public page: /issues/019dbb1d-f3d1-79d0-be89-356d1cb05fde. Public JSON: /v1/issues/019dbb1d-f3d1-79d0-be89-356d1cb05fde

ollama is stuck in a likely unclassified userspace loop: 33.33% of sampled CPU passed through _raw_spin_trylock, with repeated thread backtraces show 1 thread(s) around 0x000055c5c39ed143 in ?? () and 1 thread(s) around 0x000055c5c39ed143 in ?? ().

highscore: 106reports: 1successful triagesimilarity: 99%

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

Last seen: 2026-07-06 08:15 UTC. Public page: /issues/019ded48-a351-7db1-b2cd-e2a5a99f7943. Public JSON: /v1/issues/019ded48-a351-7db1-b2cd-e2a5a99f7943

Worker outcome summary

This issue has 5 recorded worker attempts. Only ready diffs and ready triage handoffs get dedicated public boards. Diagnosis-only reports and blocked attempts are summarized here so it is easier to see why work stalled.

3 ready triage handoffs
2 diagnosis-only reports

No ready patch attempts, failed patch attempts, explained impossible attempts, or other attempt states.

Most common blockers

  • workspace-acquisition (3 attempts)

Published attempts

diagnosis-only report

report

ollama likely remains stuck in an unclassified userspace loop. A diagnosis report and patch proposal were created locally.

state: readycreated: 2026-05-28 08:15 UTCvalidation: ready
Published session

Prompt

## Plan Pass

You are planning a fixer patch before any edits happen.

Read the evidence bundle at `./evidence.json`. The prepared workspace is `./workspace` and it was acquired via `local-executable-upstream-git`. The original pre-edit snapshot is available at `./source` if you need to inspect it. For interpreter processes, plan from the script/application entrypoint evidence first and include the runtime only as a second investigation target unless the evidence proves a runtime bug.

Validation expectation: try the project-level build/test entrypoint from the workspace root before reporting only a focused leaf compile. Detected candidate(s): `cmake -S . -B build-fix -G Ninja && cmake --build build-fix && ctest --test-dir build-fix --output-on-failure`. If the project-level command fails because dependencies or generated files are missing, include the exact command and failure reason in `## Validation`, then run the narrowest relevant compile/test that is still reproducible from a clean checkout.

Upstream-style expectation: before planning or editing, check for contribution/style docs (`CONTRIBUTING`, `HACKING`, `README-hacking`, `README.md`, `docs/`, `dev-docs/`) and scan the touched subsystem for local helpers. If the project has wrappers for file IO, path-relative IO, process spawning, memory allocation, logging, locking, or platform compatibility, prefer those wrappers over generic libc/std APIs. For public upstream review, prepare the final patch against the upstream default integration branch, usually `master` or `main`; use installed or stable source trees for reproduction/backport validation, not as the default merge-request base unless the contribution docs explicitly say to target a stable branch. Do not invent a reproducer or user-visible failure that is not in the evidence bundle; if the evidence is profiler-only or indirect, describe it as a targeted mitigation or stop with a diagnosis instead of presenting a speculative patch as a confirmed bug fix. In the plan and final validation, name any such helper, convention, branch-base choice, or evidence limit you found, or say that no relevant local helper was found. Treat this as a `github.com_ollama_ollama` upstream patch, not just a Debian-local workaround. Inspect the relevant code, nearby callers, project contribution docs, and local helper/compat APIs, but do not edit files in this pass.

Return a short markdown plan with these exact sections:

## Problem
## Evidence Confidence
## Proposed Subject
## Patch Plan
## Risks
## Validation

Classify `## Evidence Confidence` as exactly one of `reproduced`, `observed`, or `inferred`. Use `inferred` only for a no-patch diagnosis/report plan unless you can name the extra evidence you will collect before editing; inferred source patches are blocked by Fixer because they are not pull-request-ready. For `observed` source-patch plans, plan to say in the final `## Issue Connection` that the failure was observed by Fixer and not independently reproduced. If the plan touches authentication, authorization, credentials, cryptography, sandboxing, permissions, timing/throttling behavior, or PostgreSQL database-core behavior such as dynamic library resolution, extension loading, transaction semantics, locking, planner/executor behavior, catalog changes, or storage changes, treat it as high-risk: do not plan a source patch unless validation can reproduce the behavior and analyze the semantic impact; otherwise plan a no-patch diagnosis/report. The plan must explain how the proposed code change addresses the observed issue evidence, call out any prior Fixer patch that should be improved or replaced, reject awkward control flow such as avoidable `goto` if there is a cleaner bounded alternative, name any local helper APIs or maintainer conventions the patch should follow, and keep the intended maintainer-facing explanation clear enough that someone unfamiliar with the local complaint wording can still follow the fix. In `## Validation`, name the reproducible configure/build/test entrypoint you will try from the workspace root before any focused leaf compile or smoke check, and include one bounded independent reproduction attempt for the collected failure signal when it is safe and cheap. Do not plan to claim `reproduced` unless that reproduction command or test can actually show the failure.

## Patch Pass

You are working on a bounded fixer proposal.

Read the evidence bundle at `./evidence.json`. The prepared workspace is `./workspace` and it was acquired via `local-executable-upstream-git`. Produce the smallest reasonable patch for the target repository, keep the change upstreamable, prefer the clearest control flow available, and do not keep avoidable `goto` when a simpler structure would read better. Before introducing new file, process, allocation, locking, networking, or platform APIs, inspect nearby code and project contribution docs for existing helpers or compatibility wrappers and use those local patterns unless you can explain why they do not fit. Validate from a reproducible workspace-root entrypoint before falling back to focused leaf commands; if a build or test cannot run, report the exact command, the exact blocker, and any narrower check you ran instead. During validation, also try one bounded independent reproduction of the collected failure signal when it is safe and cheap, such as a failing test, smoke command, perf/strace comparison, or before/after runtime check. Only use `reproduced` if that command or test actually reproduced the failure; otherwise keep `observed` and report the reproduction blocker. The final explanation must connect the observed issue evidence to the actual code change, not just paraphrase the diff. Write like a maintainer is going to read the patch mail cold: explain the bug in plain language, define subsystem-specific jargon the first time you need it, and make the causal story obvious. Explicitly classify evidence confidence as `reproduced`, `observed`, or `inferred`: `reproduced` means you reproduced the failure locally; `observed` means Fixer has direct crash/log/trace evidence but you did not independently reproduce it; `inferred` means the source patch is not pull-request-ready, so do not leave a source diff unless you first gather stronger observed/reproduced evidence; otherwise return a no-patch diagnosis/report. For any source-changing `observed` patch, say explicitly in `## Issue Connection` that the failure was observed by Fixer and not independently reproduced. Security-sensitive areas such as authentication, authorization, credentials, cryptography, sandboxing, permissions, and timing/throttling behavior need reproduced evidence plus explicit security-impact analysis before leaving a source diff; otherwise return a no-patch diagnosis/report for human review. If you introduce non-obvious state translation, index remapping, or backend split logic, add a short source comment that explains the invariant being preserved.

Start by explaining the likely root cause from the collected perf, strace, and /proc evidence. If you cannot land a safe patch, leave a diagnosis that is strong enough for an upstream bug report.

Validation expectation: try the project-level build/test entrypoint from the workspace root before reporting only a focused leaf compile. Detected candidate(s): `cmake -S . -B build-fix -G Ninja && cmake --build build-fix && ctest --test-dir build-fix --output-on-failure`. If the project-level command fails because dependencies or generated files are missing, include the exact command and failure reason in `## Validation`, then run the narrowest relevant compile/test that is still reproducible from a clean checkout.

Upstream-style expectation: before planning or editing, check for contribution/style docs (`CONTRIBUTING`, `HACKING`, `README-hacking`, `README.md`, `docs/`, `dev-docs/`) and scan the touched subsystem for local helpers. If the project has wrappers for file IO, path-relative IO, process spawning, memory allocation, logging, locking, or platform compatibility, prefer those wrappers over generic libc/std APIs. For public upstream review, prepare the final patch against the upstream default integration branch, usually `master` or `main`; use installed or stable source trees for reproduction/backport validation, not as the default merge-request base unless the contribution docs explicitly say to target a stable branch. Do not invent a reproducer or user-visible failure that is not in the evidence bundle; if the evidence is profiler-only or indirect, describe it as a targeted mitigation or stop with a diagnosis instead of presenting a speculative patch as a confirmed bug fix. In the plan and final validation, name any such helper, convention, branch-base choice, or evidence limit you found, or say that no relevant local helper was found. Treat this as a `github.com_ollama_ollama` upstream patch, not just a Debian-local workaround. 

Keep the change narrowly scoped and summarize validation clearly.

In every authoring pass, your final response must start with `Subject: <single-line git commit subject>` and then include these markdown sections exactly:

## Commit Message
A short upstream-friendly explanation of what changed and why. Write it in plain language that a maintainer can follow without local complaint context. If you use subsystem jargon, define it immediately.

## Evidence Confidence
Exactly one word: `reproduced`, `observed`, or `inferred`. Use `reproduced` only when you reproduced the failure locally with a command or test, and include that command/test in `## Validation`. Use `observed` when Fixer has direct crash/log/trace evidence but you did not independently reproduce it. If `## Git Add Paths` lists source files for an `observed` patch, `## Issue Connection` must explicitly say the failure was observed by Fixer and not independently reproduced. Security-sensitive source changes touching authentication, authorization, credentials, cryptography, sandboxing, permissions, or timing/throttling behavior require reproduced evidence and explicit security-impact analysis. PostgreSQL database-core source changes touching dynamic library resolution, extension loading, transaction semantics, locking, planner/executor behavior, catalog changes, or storage changes require reproduced evidence plus explicit semantic-impact analysis. Otherwise list `None` under `## Git Add Paths` and write a no-patch diagnosis/report. Use `inferred` for profiler/strace/indirect evidence; inferred responses may be no-patch diagnoses or reports, but inferred source patches are not pull-request-ready until stronger evidence is gathered.

## Issue Connection
Write this as maintainer-facing patch mail, not as local Fixer notes. Cover four things explicitly in readable sentences: the user-visible symptom or the exact collected signal, the code-level cause or the cautious inference from evidence, the specific change you made, and the expected effect. Do not invent a reproducer, command line, crash, or user-visible failure that is not present in the evidence bundle. If the evidence is direct-but-not-reproduced, say it was observed by Fixer and not independently reproduced. If the evidence is indirect and you did not gather stronger evidence, do not leave a source diff; write a no-patch diagnosis/report instead. Include an explicit effect sentence such as `The expected effect is ...`, `This should reduce ...`, or `This prevents ...` for source patches. If the logic is non-obvious in code, mention that you added a short explanatory comment.

## Git Add Paths
List the repo-relative paths that belong in the final patch, one per line. Use `None` only when you intentionally made no source changes. Include intentionally new files, and do not list generated build artifacts.

## Validation
List the checks you ran, or say clearly that you could not run them. Include the independent reproduction command/test and result when `## Evidence Confidence` is `reproduced`; if reproduction was attempted but blocked, name the exact blocker and keep confidence at `observed` or `inferred`.

Before editing, read the plan at `./plan-output.txt` and follow it unless the code proves part of it wrong. If you change course, say so explicitly in the final write-up instead of silently drifting from the plan.

## Review Pass 1

You are reviewing a freshly generated fixer patch.

Read the evidence bundle at `./evidence.json`. The prepared workspace is `./workspace` and it was acquired via `local-executable-upstream-git`. Review the first patch pass. The original pre-edit snapshot is available at `./source` for diffing.

Upstream-style expectation: before planning or editing, check for contribution/style docs (`CONTRIBUTING`, `HACKING`, `README-hacking`, `README.md`, `docs/`, `dev-docs/`) and scan the touched subsystem for local helpers. If the project has wrappers for file IO, path-relative IO, process spawning, memory allocation, logging, locking, or platform compatibility, prefer those wrappers over generic libc/std APIs. For public upstream review, prepare the final patch against the upstream default integration branch, usually `master` or `main`; use installed or stable source trees for reproduction/backport validation, not as the default merge-request base unless the contribution docs explicitly say to target a stable branch. Do not invent a reproducer or user-visible failure that is not in the evidence bundle; if the evidence is profiler-only or indirect, describe it as a targeted mitigation or stop with a diagnosis instead of presenting a speculative patch as a confirmed bug fix. In the plan and final validation, name any such helper, convention, branch-base choice, or evidence limit you found, or say that no relevant local helper was found. Treat this as a `github.com_ollama_ollama` upstream patch, not just a Debian-local workaround.

Validation expectation: try the project-level build/test entrypoint from the workspace root before reporting only a focused leaf compile. Detected candidate(s): `cmake -S . -B build-fix -G Ninja && cmake --build build-fix && ctest --test-dir build-fix --output-on-failure`. If the project-level command fails because dependencies or generated files are missing, include the exact command and failure reason in `## Validation`, then run the narrowest relevant compile/test that is still reproducible from a clean checkout. The latest author response is at `./patch-output.txt`. Inspect the current code and changed paths like a strict code reviewer. Focus on correctness, regressions, maintainability, awkward control flow such as avoidable `goto`, missing validation, weak or non-gittable commit message text, and explanations that fail to connect the observed issue evidence to the code change. Also review the maintainer experience: the patch mail should be easy to accept upstream, the user-visible bug should be explained in plain language, subsystem-specific jargon should be defined when first used, and any non-obvious state translation or index remapping in code should have a short explanatory comment. Reject patches that omit `## Evidence Confidence`, use anything other than `reproduced`, `observed`, or `inferred`, or sound more certain than that evidence level allows. Reject patches that claim `reproduced` unless `## Validation` names the concrete reproduction command or test and its result. Reject source patches in security-sensitive areas such as authentication, authorization, credentials, cryptography, sandboxing, permissions, and timing/throttling behavior unless the author reproduced the behavior and explicitly analyzed the security impact of the change; observed-only evidence should become a diagnosis/report, not a PR-ready source diff. Reject patches that invent a reproducer, command line, crash, or user-visible failure not present in the evidence bundle; indirect profiler or strace evidence may justify a cautious mitigation, but the author must say it is indirect instead of presenting it as a confirmed upstream bug. Reject patches that introduce generic libc/std APIs when nearby code or project docs provide a local compat/helper API for the same job, unless the author explicitly justifies the exception. Reject validation that only reports a leaf object/syntax build when a project-level configure/build/test entrypoint exists and

[truncated 365 bytes]

Response

## Plan Pass

## Problem
Fixer observed `/usr/local/bin/ollama serve` with an indirect profiler signal: 54 threads, futex waits, process state sleeping, low sampled CPU around 0.4%, unresolved stripped frames, and no symbolized source hotspot. The raw investigation artifact directory referenced by `evidence.json` is not present, so the bundled summary cannot be tied to a specific Go function or runner path.

## Evidence Confidence
inferred

## Proposed Subject
No source patch yet: collect a symbolized `ollama serve` profile before changing scheduler or runner code.

## Patch Plan
Do not edit source in this pass. The evidence is profiler-only and classifies the loop as `unknown-userspace-loop` with confidence `0.42`, which is not enough for an upstream-ready bug fix.

Base any future patch on upstream `main`; the workspace is already on `main...origin/main`. Follow `CONTRIBUTING.md`: package-style subject, lowercase continuation title, and behavior-focused tests. Relevant local conventions/helpers found: `logutil.NewLogger`, `logutil.Trace`, `slog` structured logging, and `server/internal/internal/syncs.Group`; no file IO or process helper is relevant to the current evidence.

If additional evidence identifies a concrete scheduler/runner loop, inspect `cmd.RunServer`, `server.Serve`, `server/sched.go`, `llm/server.go`, and the active runner implementation first. Prefer a bounded structured-control fix over awkward retry `goto` flow. No prior Fixer patch is present in the workspace (`git diff` is empty), so there is nothing to replace.

## Risks
A speculative change to scheduler expiration, runner lifecycle, or background goroutine behavior would risk altering model unload timing, request cancellation, concurrency, or resource recovery without proving it addresses the observed process. The current futex-heavy sample may also be normal idle Go/runtime behavior.

## Validation
First try the project-level entrypoint from the workspace root:

```sh
cmake -S . -B build-fix -G Ninja && cmake --build build-fix && ctest --test-dir build-fix --output-on-failure
```

If that fails due to missing generated files or optional native dependencies, record the exact failure and then run the narrowest relevant check, likely `go test ./server ./llm ./cmd` or the package identified by the new symbolized hotspot.

Bounded independent reproduction attempt before any patch: run a locally built `ollama serve` with temporary `HOME`, `OLLAMA_MODELS`, and an unused localhost port, then sample CPU/thread state and, if available, a symbolized Go/pprof or perf profile. Only classify as reproduced if that command shows the same hot signal with a source-level hotspot.

## Patch Pass

Subject: diagnostics: require symbolized ollama serve profile

## Commit Message
No source patch is included. The collected signal is an unsymbolized profiler/strace sample of `ollama serve`, and it does not identify an upstream code path strongly enough for a pull-request-ready fix.

## Evidence Confidence
inferred

## Issue Connection
Fixer observed `/usr/local/bin/ollama serve` with 54 threads, repeated `futex(..., FUTEX_WAIT_PRIVATE, ...)` calls, process state `S (sleeping)`, and about 0.4% CPU. The hottest path was an unresolved offset in the stripped `ollama` binary, and the evidence classified the loop as `unknown-userspace-loop` with confidence `0.42`.

The likely root cause from the available perf, strace, and `/proc` evidence is not a proven busy loop in Ollama source. It looks more like many Go/runtime or worker threads blocked on futex waits, with a small amount of scheduler/runtime activity. Because the frames are unsymbolized and the raw investigation artifact directory is unavailable, I cannot tie the sample to `cmd.RunServer`, `server.Serve`, `server/sched.go`, `llm/server.go`, or a runner loop.

No code change was made. I followed the saved plan in `plan-output.txt`, which said not to patch without a symbolized hotspot. The expected effect is no behavior change; this avoids sending maintainers a speculative scheduler or runner lifecycle patch without source-level evidence.

Upstream conventions checked: repository branch is `main`, `CONTRIBUTING.md` asks for package-style lowercase commit subjects and behavior-focused tests, and `docs/development.md` documents `cmake`, `go run . serve`, and `go test ./...`. Relevant local patterns found include `logutil.NewLogger`, `logutil.Trace`, structured `slog`, and `server/internal/internal/syncs.Group`; no helper was applicable because no source API was introduced.

## Git Add Paths
None

## Validation
Attempted project-level validation from the workspace root:

```sh
cmake -S . -B build-fix -G Ninja && cmake --build build-fix && ctest --test-dir build-fix --output-on-failure
```

Result: failed during CMake configure. Exact blocker: `Could NOT find Vulkan (missing: glslc) (found version "1.4.341")`.

Attempted narrower relevant check:

```sh
GOCACHE=/tmp/ollama-go-build-cache GOPATH=/tmp/ollama-gopath GOTMPDIR=/tmp go test ./cmd ./server ./llm
```

Result: failed before compilation because dependencies were not cached and network is blocked. Exact blocker included `Get "https://proxy.golang.org/...": dial udp 127.0.0.53:53: socket: operation not permitted`.

Attempted bounded independent reproduction against the installed binary with temporary `HOME`, `OLLAMA_MODELS`, and nondefault `OLLAMA_HOST`:

```sh
HOME="$tmp/home" OLLAMA_MODELS="$tmp/models" OLLAMA_HOST=127.0.0.1:21435 /usr/local/bin/ollama serve
```

Result: blocked by sandbox networking before sampling. Exact blocker: `Error: listen tcp 127.0.0.1:21435: socket: operation not permitted`.

## Review Pass 1

RESULT: ok

The pass is acceptable as a no-patch diagnosis. The workspace has no source diff, which matches the `inferred` evidence level and the profiler-only evidence bundle. The response includes the required sections, does not invent a reproducer, reports the project-level CMake command and exact `glslc` blocker, and documents the narrower Go test and independent reproduction blockers.

It also names the upstream branch/conventions and relevant local helpers, and it keeps the causal claim appropriately cautious: futex waits plus low CPU and unresolved frames are not enough to justify a scheduler or runner source patch.

diagnosis-only report

report

ollama likely remains stuck in an unclassified userspace loop. A diagnosis report and patch proposal were created locally.

state: readycreated: 2026-05-28 08:15 UTCvalidation: ready
Published session

Prompt

## Plan Pass

You are planning a fixer patch before any edits happen.

Read the evidence bundle at `./evidence.json`. The prepared workspace is `./workspace` and it was acquired via `local-executable-upstream-git`. The original pre-edit snapshot is available at `./source` if you need to inspect it. For interpreter processes, plan from the script/application entrypoint evidence first and include the runtime only as a second investigation target unless the evidence proves a runtime bug.

Validation expectation: try the project-level build/test entrypoint from the workspace root before reporting only a focused leaf compile. Detected candidate(s): `cmake -S . -B build-fix -G Ninja && cmake --build build-fix && ctest --test-dir build-fix --output-on-failure`. If the project-level command fails because dependencies or generated files are missing, include the exact command and failure reason in `## Validation`, then run the narrowest relevant compile/test that is still reproducible from a clean checkout.

Upstream-style expectation: before planning or editing, check for contribution/style docs (`CONTRIBUTING`, `HACKING`, `README-hacking`, `README.md`, `docs/`, `dev-docs/`) and scan the touched subsystem for local helpers. If the project has wrappers for file IO, path-relative IO, process spawning, memory allocation, logging, locking, or platform compatibility, prefer those wrappers over generic libc/std APIs. For public upstream review, prepare the final patch against the upstream default integration branch, usually `master` or `main`; use installed or stable source trees for reproduction/backport validation, not as the default merge-request base unless the contribution docs explicitly say to target a stable branch. Do not invent a reproducer or user-visible failure that is not in the evidence bundle; if the evidence is profiler-only or indirect, describe it as a targeted mitigation or stop with a diagnosis instead of presenting a speculative patch as a confirmed bug fix. In the plan and final validation, name any such helper, convention, branch-base choice, or evidence limit you found, or say that no relevant local helper was found. Treat this as a `github.com_ollama_ollama` upstream patch, not just a Debian-local workaround. Inspect the relevant code, nearby callers, project contribution docs, and local helper/compat APIs, but do not edit files in this pass.

Return a short markdown plan with these exact sections:

## Problem
## Evidence Confidence
## Proposed Subject
## Patch Plan
## Risks
## Validation

Classify `## Evidence Confidence` as exactly one of `reproduced`, `observed`, or `inferred`. Use `inferred` only for a no-patch diagnosis/report plan unless you can name the extra evidence you will collect before editing; inferred source patches are blocked by Fixer because they are not pull-request-ready. For `observed` source-patch plans, plan to say in the final `## Issue Connection` that the failure was observed by Fixer and not independently reproduced. If the plan touches authentication, authorization, credentials, cryptography, sandboxing, permissions, timing/throttling behavior, or PostgreSQL database-core behavior such as dynamic library resolution, extension loading, transaction semantics, locking, planner/executor behavior, catalog changes, or storage changes, treat it as high-risk: do not plan a source patch unless validation can reproduce the behavior and analyze the semantic impact; otherwise plan a no-patch diagnosis/report. The plan must explain how the proposed code change addresses the observed issue evidence, call out any prior Fixer patch that should be improved or replaced, reject awkward control flow such as avoidable `goto` if there is a cleaner bounded alternative, name any local helper APIs or maintainer conventions the patch should follow, and keep the intended maintainer-facing explanation clear enough that someone unfamiliar with the local complaint wording can still follow the fix. In `## Validation`, name the reproducible configure/build/test entrypoint you will try from the workspace root before any focused leaf compile or smoke check, and include one bounded independent reproduction attempt for the collected failure signal when it is safe and cheap. Do not plan to claim `reproduced` unless that reproduction command or test can actually show the failure.

## Patch Pass

You are working on a bounded fixer proposal.

Read the evidence bundle at `./evidence.json`. The prepared workspace is `./workspace` and it was acquired via `local-executable-upstream-git`. Produce the smallest reasonable patch for the target repository, keep the change upstreamable, prefer the clearest control flow available, and do not keep avoidable `goto` when a simpler structure would read better. Before introducing new file, process, allocation, locking, networking, or platform APIs, inspect nearby code and project contribution docs for existing helpers or compatibility wrappers and use those local patterns unless you can explain why they do not fit. Validate from a reproducible workspace-root entrypoint before falling back to focused leaf commands; if a build or test cannot run, report the exact command, the exact blocker, and any narrower check you ran instead. During validation, also try one bounded independent reproduction of the collected failure signal when it is safe and cheap, such as a failing test, smoke command, perf/strace comparison, or before/after runtime check. Only use `reproduced` if that command or test actually reproduced the failure; otherwise keep `observed` and report the reproduction blocker. The final explanation must connect the observed issue evidence to the actual code change, not just paraphrase the diff. Write like a maintainer is going to read the patch mail cold: explain the bug in plain language, define subsystem-specific jargon the first time you need it, and make the causal story obvious. Explicitly classify evidence confidence as `reproduced`, `observed`, or `inferred`: `reproduced` means you reproduced the failure locally; `observed` means Fixer has direct crash/log/trace evidence but you did not independently reproduce it; `inferred` means the source patch is not pull-request-ready, so do not leave a source diff unless you first gather stronger observed/reproduced evidence; otherwise return a no-patch diagnosis/report. For any source-changing `observed` patch, say explicitly in `## Issue Connection` that the failure was observed by Fixer and not independently reproduced. Security-sensitive areas such as authentication, authorization, credentials, cryptography, sandboxing, permissions, and timing/throttling behavior need reproduced evidence plus explicit security-impact analysis before leaving a source diff; otherwise return a no-patch diagnosis/report for human review. If you introduce non-obvious state translation, index remapping, or backend split logic, add a short source comment that explains the invariant being preserved.

Start by explaining the likely root cause from the collected perf, strace, and /proc evidence. If you cannot land a safe patch, leave a diagnosis that is strong enough for an upstream bug report.

Validation expectation: try the project-level build/test entrypoint from the workspace root before reporting only a focused leaf compile. Detected candidate(s): `cmake -S . -B build-fix -G Ninja && cmake --build build-fix && ctest --test-dir build-fix --output-on-failure`. If the project-level command fails because dependencies or generated files are missing, include the exact command and failure reason in `## Validation`, then run the narrowest relevant compile/test that is still reproducible from a clean checkout.

Upstream-style expectation: before planning or editing, check for contribution/style docs (`CONTRIBUTING`, `HACKING`, `README-hacking`, `README.md`, `docs/`, `dev-docs/`) and scan the touched subsystem for local helpers. If the project has wrappers for file IO, path-relative IO, process spawning, memory allocation, logging, locking, or platform compatibility, prefer those wrappers over generic libc/std APIs. For public upstream review, prepare the final patch against the upstream default integration branch, usually `master` or `main`; use installed or stable source trees for reproduction/backport validation, not as the default merge-request base unless the contribution docs explicitly say to target a stable branch. Do not invent a reproducer or user-visible failure that is not in the evidence bundle; if the evidence is profiler-only or indirect, describe it as a targeted mitigation or stop with a diagnosis instead of presenting a speculative patch as a confirmed bug fix. In the plan and final validation, name any such helper, convention, branch-base choice, or evidence limit you found, or say that no relevant local helper was found. Treat this as a `github.com_ollama_ollama` upstream patch, not just a Debian-local workaround. 

Keep the change narrowly scoped and summarize validation clearly.

In every authoring pass, your final response must start with `Subject: <single-line git commit subject>` and then include these markdown sections exactly:

## Commit Message
A short upstream-friendly explanation of what changed and why. Write it in plain language that a maintainer can follow without local complaint context. If you use subsystem jargon, define it immediately.

## Evidence Confidence
Exactly one word: `reproduced`, `observed`, or `inferred`. Use `reproduced` only when you reproduced the failure locally with a command or test, and include that command/test in `## Validation`. Use `observed` when Fixer has direct crash/log/trace evidence but you did not independently reproduce it. If `## Git Add Paths` lists source files for an `observed` patch, `## Issue Connection` must explicitly say the failure was observed by Fixer and not independently reproduced. Security-sensitive source changes touching authentication, authorization, credentials, cryptography, sandboxing, permissions, or timing/throttling behavior require reproduced evidence and explicit security-impact analysis. PostgreSQL database-core source changes touching dynamic library resolution, extension loading, transaction semantics, locking, planner/executor behavior, catalog changes, or storage changes require reproduced evidence plus explicit semantic-impact analysis. Otherwise list `None` under `## Git Add Paths` and write a no-patch diagnosis/report. Use `inferred` for profiler/strace/indirect evidence; inferred responses may be no-patch diagnoses or reports, but inferred source patches are not pull-request-ready until stronger evidence is gathered.

## Issue Connection
Write this as maintainer-facing patch mail, not as local Fixer notes. Cover four things explicitly in readable sentences: the user-visible symptom or the exact collected signal, the code-level cause or the cautious inference from evidence, the specific change you made, and the expected effect. Do not invent a reproducer, command line, crash, or user-visible failure that is not present in the evidence bundle. If the evidence is direct-but-not-reproduced, say it was observed by Fixer and not independently reproduced. If the evidence is indirect and you did not gather stronger evidence, do not leave a source diff; write a no-patch diagnosis/report instead. Include an explicit effect sentence such as `The expected effect is ...`, `This should reduce ...`, or `This prevents ...` for source patches. If the logic is non-obvious in code, mention that you added a short explanatory comment.

## Git Add Paths
List the repo-relative paths that belong in the final patch, one per line. Use `None` only when you intentionally made no source changes. Include intentionally new files, and do not list generated build artifacts.

## Validation
List the checks you ran, or say clearly that you could not run them. Include the independent reproduction command/test and result when `## Evidence Confidence` is `reproduced`; if reproduction was attempted but blocked, name the exact blocker and keep confidence at `observed` or `inferred`.

Before editing, read the plan at `./plan-output.txt` and follow it unless the code proves part of it wrong. If you change course, say so explicitly in the final write-up instead of silently drifting from the plan.

## Review Pass 1

You are reviewing a freshly generated fixer patch.

Read the evidence bundle at `./evidence.json`. The prepared workspace is `./workspace` and it was acquired via `local-executable-upstream-git`. Review the first patch pass. The original pre-edit snapshot is available at `./source` for diffing.

Upstream-style expectation: before planning or editing, check for contribution/style docs (`CONTRIBUTING`, `HACKING`, `README-hacking`, `README.md`, `docs/`, `dev-docs/`) and scan the touched subsystem for local helpers. If the project has wrappers for file IO, path-relative IO, process spawning, memory allocation, logging, locking, or platform compatibility, prefer those wrappers over generic libc/std APIs. For public upstream review, prepare the final patch against the upstream default integration branch, usually `master` or `main`; use installed or stable source trees for reproduction/backport validation, not as the default merge-request base unless the contribution docs explicitly say to target a stable branch. Do not invent a reproducer or user-visible failure that is not in the evidence bundle; if the evidence is profiler-only or indirect, describe it as a targeted mitigation or stop with a diagnosis instead of presenting a speculative patch as a confirmed bug fix. In the plan and final validation, name any such helper, convention, branch-base choice, or evidence limit you found, or say that no relevant local helper was found. Treat this as a `github.com_ollama_ollama` upstream patch, not just a Debian-local workaround.

Validation expectation: try the project-level build/test entrypoint from the workspace root before reporting only a focused leaf compile. Detected candidate(s): `cmake -S . -B build-fix -G Ninja && cmake --build build-fix && ctest --test-dir build-fix --output-on-failure`. If the project-level command fails because dependencies or generated files are missing, include the exact command and failure reason in `## Validation`, then run the narrowest relevant compile/test that is still reproducible from a clean checkout. The latest author response is at `./patch-output.txt`. Inspect the current code and changed paths like a strict code reviewer. Focus on correctness, regressions, maintainability, awkward control flow such as avoidable `goto`, missing validation, weak or non-gittable commit message text, and explanations that fail to connect the observed issue evidence to the code change. Also review the maintainer experience: the patch mail should be easy to accept upstream, the user-visible bug should be explained in plain language, subsystem-specific jargon should be defined when first used, and any non-obvious state translation or index remapping in code should have a short explanatory comment. Reject patches that omit `## Evidence Confidence`, use anything other than `reproduced`, `observed`, or `inferred`, or sound more certain than that evidence level allows. Reject patches that claim `reproduced` unless `## Validation` names the concrete reproduction command or test and its result. Reject source patches in security-sensitive areas such as authentication, authorization, credentials, cryptography, sandboxing, permissions, and timing/throttling behavior unless the author reproduced the behavior and explicitly analyzed the security impact of the change; observed-only evidence should become a diagnosis/report, not a PR-ready source diff. Reject patches that invent a reproducer, command line, crash, or user-visible failure not present in the evidence bundle; indirect profiler or strace evidence may justify a cautious mitigation, but the author must say it is indirect instead of presenting it as a confirmed upstream bug. Reject patches that introduce generic libc/std APIs when nearby code or project docs provide a local compat/helper API for the same job, unless the author explicitly justifies the exception. Reject validation that only reports a leaf object/syntax build when a project-level configure/build/test entrypoint exists and

[truncated 365 bytes]

Response

## Plan Pass

## Problem
Fixer observed `/usr/local/bin/ollama serve` with an indirect profiler signal: 54 threads, futex waits, process state sleeping, low sampled CPU around 0.4%, unresolved stripped frames, and no symbolized source hotspot. The raw investigation artifact directory referenced by `evidence.json` is not present, so the bundled summary cannot be tied to a specific Go function or runner path.

## Evidence Confidence
inferred

## Proposed Subject
No source patch yet: collect a symbolized `ollama serve` profile before changing scheduler or runner code.

## Patch Plan
Do not edit source in this pass. The evidence is profiler-only and classifies the loop as `unknown-userspace-loop` with confidence `0.42`, which is not enough for an upstream-ready bug fix.

Base any future patch on upstream `main`; the workspace is already on `main...origin/main`. Follow `CONTRIBUTING.md`: package-style subject, lowercase continuation title, and behavior-focused tests. Relevant local conventions/helpers found: `logutil.NewLogger`, `logutil.Trace`, `slog` structured logging, and `server/internal/internal/syncs.Group`; no file IO or process helper is relevant to the current evidence.

If additional evidence identifies a concrete scheduler/runner loop, inspect `cmd.RunServer`, `server.Serve`, `server/sched.go`, `llm/server.go`, and the active runner implementation first. Prefer a bounded structured-control fix over awkward retry `goto` flow. No prior Fixer patch is present in the workspace (`git diff` is empty), so there is nothing to replace.

## Risks
A speculative change to scheduler expiration, runner lifecycle, or background goroutine behavior would risk altering model unload timing, request cancellation, concurrency, or resource recovery without proving it addresses the observed process. The current futex-heavy sample may also be normal idle Go/runtime behavior.

## Validation
First try the project-level entrypoint from the workspace root:

```sh
cmake -S . -B build-fix -G Ninja && cmake --build build-fix && ctest --test-dir build-fix --output-on-failure
```

If that fails due to missing generated files or optional native dependencies, record the exact failure and then run the narrowest relevant check, likely `go test ./server ./llm ./cmd` or the package identified by the new symbolized hotspot.

Bounded independent reproduction attempt before any patch: run a locally built `ollama serve` with temporary `HOME`, `OLLAMA_MODELS`, and an unused localhost port, then sample CPU/thread state and, if available, a symbolized Go/pprof or perf profile. Only classify as reproduced if that command shows the same hot signal with a source-level hotspot.

## Patch Pass

Subject: diagnostics: require symbolized ollama serve profile

## Commit Message
No source patch is included. The collected signal is an unsymbolized profiler/strace sample of `ollama serve`, and it does not identify an upstream code path strongly enough for a pull-request-ready fix.

## Evidence Confidence
inferred

## Issue Connection
Fixer observed `/usr/local/bin/ollama serve` with 54 threads, repeated `futex(..., FUTEX_WAIT_PRIVATE, ...)` calls, process state `S (sleeping)`, and about 0.4% CPU. The hottest path was an unresolved offset in the stripped `ollama` binary, and the evidence classified the loop as `unknown-userspace-loop` with confidence `0.42`.

The likely root cause from the available perf, strace, and `/proc` evidence is not a proven busy loop in Ollama source. It looks more like many Go/runtime or worker threads blocked on futex waits, with a small amount of scheduler/runtime activity. Because the frames are unsymbolized and the raw investigation artifact directory is unavailable, I cannot tie the sample to `cmd.RunServer`, `server.Serve`, `server/sched.go`, `llm/server.go`, or a runner loop.

No code change was made. I followed the saved plan in `plan-output.txt`, which said not to patch without a symbolized hotspot. The expected effect is no behavior change; this avoids sending maintainers a speculative scheduler or runner lifecycle patch without source-level evidence.

Upstream conventions checked: repository branch is `main`, `CONTRIBUTING.md` asks for package-style lowercase commit subjects and behavior-focused tests, and `docs/development.md` documents `cmake`, `go run . serve`, and `go test ./...`. Relevant local patterns found include `logutil.NewLogger`, `logutil.Trace`, structured `slog`, and `server/internal/internal/syncs.Group`; no helper was applicable because no source API was introduced.

## Git Add Paths
None

## Validation
Attempted project-level validation from the workspace root:

```sh
cmake -S . -B build-fix -G Ninja && cmake --build build-fix && ctest --test-dir build-fix --output-on-failure
```

Result: failed during CMake configure. Exact blocker: `Could NOT find Vulkan (missing: glslc) (found version "1.4.341")`.

Attempted narrower relevant check:

```sh
GOCACHE=/tmp/ollama-go-build-cache GOPATH=/tmp/ollama-gopath GOTMPDIR=/tmp go test ./cmd ./server ./llm
```

Result: failed before compilation because dependencies were not cached and network is blocked. Exact blocker included `Get "https://proxy.golang.org/...": dial udp 127.0.0.53:53: socket: operation not permitted`.

Attempted bounded independent reproduction against the installed binary with temporary `HOME`, `OLLAMA_MODELS`, and nondefault `OLLAMA_HOST`:

```sh
HOME="$tmp/home" OLLAMA_MODELS="$tmp/models" OLLAMA_HOST=127.0.0.1:21435 /usr/local/bin/ollama serve
```

Result: blocked by sandbox networking before sampling. Exact blocker: `Error: listen tcp 127.0.0.1:21435: socket: operation not permitted`.

## Review Pass 1

RESULT: ok

The pass is acceptable as a no-patch diagnosis. The workspace has no source diff, which matches the `inferred` evidence level and the profiler-only evidence bundle. The response includes the required sections, does not invent a reproducer, reports the project-level CMake command and exact `glslc` blocker, and documents the narrower Go test and independent reproduction blockers.

It also names the upstream branch/conventions and relevant local helpers, and it keeps the causal claim appropriately cautious: futex waits plus low CPU and unresolved frames are not enough to justify a scheduler or runner source patch.

ready triage handoff

triage

ollama likely remains stuck in an unclassified userspace loop. A diagnosis report and external handoff were created locally.

state: readycreated: 2026-05-27 05:09 UTCvalidation: ready

Why it stopped

workspace-acquisition

Handoff

Likely owner: local executable ollama

Reason: workspace-acquisition

Suggested bug target: https://github.com/ollama/ollama.git

  • Use the source repository identified from the executable metadata (https://github.com/ollama/ollama.git) before asking Fixer for a patch.
  • Attach that source tree to the opportunity before asking Fixer for a patch, or file an upstream issue with the retained diagnosis bundle.
  • Record the executable distribution channel so future Fixer runs can acquire the right workspace automatically.

ready triage handoff

triage

ollama likely remains stuck in an unclassified userspace loop. A diagnosis report was created even though no patchable workspace was available: opportunity 92080 has no repo root, package name, or source package

state: readycreated: 2026-05-26 01:17 UTCvalidation: ready

Why it stopped

workspace-acquisition

Handoff

Likely owner: local executable ollama

Reason: workspace-acquisition

  • Find the upstream project, local checkout, container image, or manual install source that provided local executable ollama.
  • Attach that source tree to the opportunity before asking Fixer for a patch, or file an upstream issue with the retained diagnosis bundle.
  • Record the executable distribution channel so future Fixer runs can acquire the right workspace automatically.

ready triage handoff

triage

ollama likely remains stuck in an unclassified userspace loop. A diagnosis report and external handoff were created locally.

state: readycreated: 2026-05-26 01:17 UTCvalidation: ready

Why it stopped

workspace-acquisition

Handoff

Likely owner: local executable ollama

Reason: workspace-acquisition

Suggested bug target: https://github.com/ollama/ollama.git

  • Use the source repository identified from the executable metadata (https://github.com/ollama/ollama.git) before asking Fixer for a patch.
  • Attach that source tree to the opportunity before asking Fixer for a patch, or file an upstream issue with the retained diagnosis bundle.
  • Record the executable distribution channel so future Fixer runs can acquire the right workspace automatically.