redis-check-rdb likely remains stuck in a busy-poll loop. The diagnosis was captured, but the patch proposal did not complete cleanly.
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 `debian-source`. 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): `make` and, if available, `make check`. 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. 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, or evidence limit you found, or say that no relevant local helper was found. Treat this as a `redis` 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. 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 `debian-source`. 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. 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.
A previous Fixer patch attempt already exists for this issue. It was generated by Fixer `0.148.0`. Review that patch before changing code, improve it instead of starting blind, and clean up anything awkward or underexplained. In particular, remove avoidable `goto`, tighten the explanation of what the patch is doing, and make the resulting diff feel ready for upstream git review.
- Prior patch: `./prior-best.patch`
- Prior published session: `./prior-best-session.md`
Validation expectation: try the project-level build/test entrypoint from the workspace root before reporting only a focused leaf compile. Detected candidate(s): `make` and, if available, `make check`. 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. 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, or evidence limit you found, or say that no relevant local helper was found. Treat this as a `redis` 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. 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 `debian-source`. Review the first patch pass. The original pre-edit snapshot is available at `./source` for diffing. The workspace currently changes these repo-relative paths: src/server.c. Verify that `## Git Add Paths` matches this exact set and that `## Issue Connection` explains every shipped functional file.
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. 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, or evidence limit you found, or say that no relevant local helper was found. Treat this as a `redis` 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): `make` and, if available, `make check`. 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 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 was not attempted; if a full build cannot run, the author must show the exact failed command and blocker.
Do not apply code changes in this pass.
Return a short markdown review report. The first non-empty line must be exactly one of:
RESULT: ok
RESULT: fix-needed
If you choose `RESULT: fix-needed`, add a `## Findings` section with concrete, actionable items.
## Refinement Pass 1
You are refining a fixer patch after an explicit code review.
Read the evidence bundle at `./evidence.json`. The prepared workspace is `./workspace` and it was acquired via `debian-source`. Read the latest author response at `./patch-output.txt`. Read the review report at `./review-1-output.txt`. This is refinement round 1. The original pre-edit snapshot is available at `./source` if you need to compare the current patch against it. Re-read the planning pass at `./plan-output.txt` before editing. The workspace currently changes these repo-relative paths: src/server.c. Either keep that exact set synchronized with `## Git Add Paths` and `## Issue Connection`, or revert any unintended file before you answer.
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. 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, or evidence limit you found, or say that no relevant local helper was found. Treat this as a `redis` 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): `make` and, if available, `make check`. 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 narrow
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Response
## Plan Pass
## Problem
Fixer observed a Redis server process waking from `epoll_wait` about every 100 ms and immediately reading `/proc/self/stat`. The evidence labels `redis-check-rdb`, but the command line and thread name are `redis-server`, so the relevant entrypoint is the server event loop. The matching source path is `serverCron()` -> `cronUpdateMemoryStats()` -> `zmalloc_get_rss()`, whose local comment says it is not designed to be fast.
## Evidence Confidence
observed
## Proposed Subject
server: reduce idle memory stat sampling
## Patch Plan
Update `src/server.c` so `cronUpdateMemoryStats()` keeps `updatePeakMemory()` at the normal cron cadence, but moves the slower RSS and allocator-stat sampling block from `run_with_period(100)` to `run_with_period(1000)`.
This follows Redis’ existing `serverCron` throttling convention, `run_with_period(...)`, and mitigates the observed `/proc/self/stat` polling without adding new file I/O or platform APIs. No relevant local helper beyond the existing `run_with_period` convention and `zmalloc_get_rss()` API is needed.
A prior Fixer patch already made the same narrow code change in `prior-best.patch`; I would keep the core behavior, improve the maintainer-facing explanation, and avoid any awkward control flow such as `goto` since a single bounded periodic block is cleaner.
## Risks
`INFO memory` and `MEMORY STATS` RSS/allocator fields may be up to about one second stale instead of about 100 ms stale. Peak memory tracking remains unchanged. Tests or callers expecting sub-second RSS refresh could need bounded waits, though I did not find a direct test asserting that freshness.
## Validation
From the workspace root, try project-level validation first:
`make`
Then try the available project test entrypoint:
`make check`
If that fails because dependencies, generated files, or sandbox limits are missing, record the exact command and failure reason, then run the focused fallback:
`make -C src redis-server`
Bounded independent signal check, if safe and available:
`timeout 4s strace -f -e trace=epoll_wait,openat,read,close -o /tmp/redis-rss.strace ./src/redis-server --port 0 --save "" --appendonly no --daemonize no`
Then count the collected signal:
`grep -c '"/proc/self/stat"' /tmp/redis-rss.strace`
Only claim `reproduced` if that check demonstrates the pre-patch `/proc/self/stat` cadence locally; otherwise final output should state the issue was observed by Fixer and not independently reproduced.
## Patch Pass
Subject: server: reduce idle memory stat sampling
## Commit Message
Redis server cron is the periodic maintenance callback. Fixer observed an idle server waking from `epoll_wait` and reading `/proc/self/stat`, which matches the memory-stat path where `serverCron()` calls `cronUpdateMemoryStats()` and Linux RSS sampling uses `zmalloc_get_rss()`.
Sample the slow cached RSS and allocator metrics once per second instead of every 100 ms, using Redis’ existing `run_with_period(...)` cron helper. Peak memory tracking still runs on every cron pass.
## Evidence Confidence
observed
## Issue Connection
Fixer observed a Redis process with repeated `epoll_wait` timeouts followed by `openat`, `read`, and `close` on `/proc/self/stat`. This failure signal was observed by Fixer and not independently reproduced.
The likely code-level cause is the cron memory-stat path: `serverCron()` calls `cronUpdateMemoryStats()`, and that function sampled RSS and allocator metrics every 100 ms. On Linux, RSS sampling uses `zmalloc_get_rss()`, which reads `/proc/self/stat` and is documented locally as not designed to be fast.
I changed that cached memory-stat block from `run_with_period(100)` to `run_with_period(1000)` and updated the nearby comment. This follows Redis’ existing `run_with_period(...)` convention; no new file I/O, process, allocation, locking, networking, or platform API was introduced. I reviewed the prior Fixer patch and kept its narrow behavior while tightening the maintainer-facing explanation.
The expected effect is to reduce idle `/proc/self/stat` reads and allocator-stat refresh work by about 10x, while keeping `INFO memory` and `MEMORY STATS` cached values refreshed once per second.
## Git Add Paths
src/server.c
## Validation
`make` from the workspace root: passed. It built Redis and test modules successfully; the dependency clean phase printed a non-fatal jemalloc `tests: No such file or directory` line and continued.
`make check` from the workspace root: failed before tests ran because the test harness could not allocate a local port: `Can't find a non busy port in the 21079-21110 range.`
Focused fallback, `make -C src redis-server`: passed; `redis-server` was up to date after the full build.
Independent signal check attempted: `timeout 4s strace -f -e trace=epoll_wait,openat,read,close -o /tmp/redis-rss.strace ./src/redis-server --port 0 --save "" --appendonly no --daemonize no`. It was blocked by sandbox ptrace restrictions: `PTRACE_TRACEME: Operation not permitted` and `ptrace(PTRACE_SEIZE, 5): Operation not permitted`, so evidence confidence remains `observed`.
## Review Pass 1
RESULT: fix-needed
## Findings
- [src/server.c](./workspace/src/server.c:1428): changing cached RSS/allocator sampling from 100 ms to 1000 ms leaves existing memory-efficiency tests with stale timing assumptions. For example, [tests/unit/memefficiency.tcl](./workspace/tests/unit/memefficiency.tcl:102) and [tests/unit/moduleapi/datatype.tcl](./workspace/tests/unit/moduleapi/datatype.tcl:157) still wait only `after 120` before asserting `allocator_frag_ratio`/`allocator_active`, with comments saying serverCron updates the info every 100 ms. After this patch, those assertions can read stale `server.cron_malloc_stats` for up to about one second. Update the affected waits/comments or use a bounded wait-for-fresh-stats pattern so the changed cadence is reflected in the test suite.
The changed path set is exactly `src/server.c`, and `## Git Add Paths` matches it. The patch uses Redis’ existing `run_with_period(...)` convention and introduces no awkward control flow or new APIs. The maintainer explanation and evidence confidence are otherwise acceptable, and validation correctly reports root `make`, blocked `make check`, and blocked `strace`.
## Refinement Pass 1
## Workflow Note
{"type":"item.completed","item":{"id":"item_4","type":"command_execution","command":"/bin/bash -lc 'git status --short && git diff -- src/server.c'","aggregated_output":" M src/server.c\ndiff --git a/src/server.c b/src/server.c\nindex 241fe69..f175633 100644\n--- a/src/server.c\n+++ b/src/server.c\n@@ -1425,8 +1425,8 @@ void updatePeakMemory(void) {\n void cronUpdateMemoryStats(void) {\n updatePeakMemory();\n \n- run_with_period(100) {\n- /* Sample the RSS and other metrics here since this is a relatively slow call.\n+ run_with_period(1000) {\n+ /* Sample the RSS and other metrics once per second since this is a relatively slow call.\n * We must sample the zmalloc_used at the same time we take the rss, otherwise\n * the frag ratio calculate may be off (ratio of two samples at different times) */\n server.cron_malloc_stats.process_rss = zmalloc_get_rss();\n","exit_code":0,"status":"completed"}}
{"type":"error","message":"Reconnecting... 1/5 (stream disconnected before completion: error sending request for url (http://127.0.0.1:2455/backend-api/codex/responses))"}
{"type":"error","message":"Reconnecting... 2/5 (stream disconnected before completion: error sending request for url (http://127.0.0.1:2455/backend-api/codex/responses))"}
{"type":"error","message":"Reconnecting... 3/5 (stream disconnected before completion: error sending request for url (http://127.0.0.1:2455/backend-api/codex/responses))"}
{"type":"error","message":"Reconnecting... 4/5 (stream disconnected before completion: error sending request for url (http://127.0.0.1:2455/backend-api/codex/responses))"}
{"type":"error","message":"Reconnecting... 5/5 (stream disconnected before completion: error sending request for url (http://127.0.0.1:2455/backend-api/codex/responses))"}
{"type":"error","message":"stream disconnected before completion: error sending request for url (http://127.0.0.1:2455/backend-api/codex/responses)"}
{"type":"turn.failed","error":{"message":"stream disconnected before completion: error sending request for url (http://127.0.0.1:2455/backend-api/codex/responses)"}}
Diff
diff --git a/src/server.c b/src/server.c
index 241fe69..f175633 100644
--- a/src/server.c
+++ b/src/server.c
@@ -1425,8 +1425,8 @@ void updatePeakMemory(void) {
void cronUpdateMemoryStats(void) {
updatePeakMemory();
- run_with_period(100) {
- /* Sample the RSS and other metrics here since this is a relatively slow call.
+ run_with_period(1000) {
+ /* Sample the RSS and other metrics once per second since this is a relatively slow call.
* We must sample the zmalloc_used at the same time we take the rss, otherwise
* the frag ratio calculate may be off (ratio of two samples at different times) */
server.cron_malloc_stats.process_rss = zmalloc_get_rss();