sandbox:read-only (macOS Seatbelt)
-- reasoning --
The user wants me to review a pull request diff and report only defects I can point at a specific line for. Let me carefully read the changed files and understand the code.

I'll inspect the PR diff against the checked-out files under `pr/`, starting with the new sweep logic and the call sites that wire it in.
└ 150 tok ·  37.3 tok/s · 12K ctx · 1597ms ttft ·  4.0s wall
↳ glob_files: glob pr/services/proxy/src/**/*.rs in .
└ glob_files: glob complete
↳ search_files: search pr/services/proxy/src for IndexEntry|BlobStore|remove|incoming|blobs/sha256
└ search_files: search complete
↳ list_dir: list pr
└ list_dir: listing complete
auto-compress is on at 85% but the context window of "x-ai/grok-4.5" on openrouter is unknown, so this run will not compress - set AFI_SOURCE_OPENROUTER_CONTEXT_WINDOW (or pass --context-window) to enable it
-- reasoning --
I need to carefully review the sweep implementation and related code. Let me read the key files.
Reading the sweep implementation and the store/metrics/admin paths it depends on.
└ 163 tok ·  58.1 tok/s · 14K ctx ·  928ms ttft ·  2.8s wall
↳ read_file: read pr/services/proxy/src/sweep.rs
└ read_file: read complete
↳ read_file: read pr/services/proxy/src/store.rs
└ read_file: read complete
↳ read_file: read pr/services/proxy/src/metrics.rs
└ read_file: read complete
↳ read_file: read pr/services/proxy/src/routes/admin.rs
└ read_file: read complete
↳ read_file: read pr/services/proxy/src/main.rs
└ read_file: read complete
↳ read_file: read pr/services/proxy/src/config.rs
└ read_file: read complete
-- reasoning --
I've found several potential bugs. Let me analyze them carefully:
🔴 `bug` services/proxy/src/metrics.rs:50: COUNTERS array order [sweep_bytes_reclaimed, sweep_blobs_removed] does not match values() return order [sweep_bytes_reclaimed, sweep_blobs_removed] - metrics exposition will swap the two counters

🔴 `bug` services/proxy src/sweep.rs:102: candidates.sort_by_key(|candidate| candidate.age) sorts youngest first but comment claims oldest first - will evict recently used packages first

🔴 `bug` services/proxy/src/routes/admin.rs:76: admin::sweep calls app.sweeper.sweep(dry_run) directly without acquiring Mutex, violating "one sweep at a time" guarantee documented in sweep.rs

🔴 `bug` services/proxy/src/sweep.rs:140: forget(&index, &gone) is called unconditionally even for dry_run=true - removes stale index entries during dry-run

🔴 `bug` services/proxy/src s/sweep.rs:224: clear_partials deletes all files in incoming directory without age check - can delete in-progress BlobWriter files, causing rename commit to fail with ENOENT

🔴 `bug` services/proxy/src/sweep.
Checking a few more call-site and sort/age details, plus whether `Duration::from_hours`/`from_mins` are available here.

└ 1464 tok ·  53.7 tok/s · 33K ctx · 2325ms ttft · 27.3s wall
↳ read_file: read pr/services/proxy/src/routes/mod.rs
└ read_file: read complete
↳ read_file: read pr/services/proxy/Cargo.toml
└ read_file: read complete
↳ search_files: search pr for from_hours|from_mins|rust-version|editions
└ search_files: search complete
↳ search_files: search pr for sweep|Sweeper|clear_partials|dry_run
└ search_files: search complete
↳ read_file: read pr/services/proxy/src/digest.rs
└ read_file: read complete
-- reasoning --
I've found several concrete defects. Let me carefully analyze them:
🔴 `bug` services/proxy/src/metrics.rs:45: COUNTERS array order does not match values() return order, so Prometheus labels are swapped
🔴 `bug` services/proxy/src/metrics.rs:77: record_sweep() calls fetch_add in wrong order (bytes before blobs) compared to COUNTERS
 🔴 `bug` services/proxy/src/metrics.rs:23: COUNTERS[4] is sweep_blobs_removed_total but values()[4] is sweep_bytes_reclaimed
🔴 `bug` services/proxy/src/sweep.rs:98: candidates.sort_by_key(|candidate| candidate.age) sorts youngest-first when over ceiling, violating "oldest first" comment
🔴 `bug` services/proxy/src/sweep.rs:98: sort_by_key ascending on Duration (larger = older) removes newest eligible blobs first
🔴 `bug` services/proxy/src/sweep.rs:102: eviction loop processes candidates in youngest-first order, breaking LRU semantics
🔴 `bug` services/proxy/src/sweep.rs:166: forget() is called unconditionally after sweep even when dry_run=true, deleting index entries for blobs that still exist
🔴 `bug` services/proxy/src/sweep.rs:166: dry_run=true still mutates index by calling forget(&index, &gone) for capacity-evicted blobs
🔴 `bug` services/proxy/src/sweep.rs:166: dry_run=true deletes index entries while leaving blobs, causing subsequent cache misses and refetches
🔴 `bug` services/proxy/src/sweep.rs:166: dry_run=true removes index entries for blobs that sweep claims to have removed
🔴 `bug` services/proxy/src/sweep.rs:102: remove failure path still decrements remaining, adds to bytes/removed, and calls forget() for blobs that still exist
🔴 `bug` services/proxy/src/sweep.rs:102: if fs remove_file fails, the blob is still counted as removed and its index entry is deleted
🔴 `bug` services/proxy/src/sweep.rs:166: forget() is called even for blobs that failed to remove, causing index loss for still-present blobs
🔴 `bug` services/proxy/src/sweep.rs: 98: age_of() uses modified time, not access time, so hot cache hits (fetched this morning) become eligible for eviction after min_age
🔴 `bug` services/proxy/src/sweep.
Checking the cache write path and a few more race-related details.
└ 2632 tok ·  52.1 tok/s · 40K ctx · 3310ms ttft · 50.6s wall
↳ read_file: read pr/services/proxy/src/routes/cache.rs
└ read_file: read complete
↳ search_files: search pr/services/proxy for spawn_blocking|last_accessed|accessed\(|modified\(
└ search_files: search complete
↳ read_file: read pr/services/proxy/src/metrics.rs
└ read_file: read complete
-- reasoning --
I've found several concrete defects. Let me carefully verify each one:
🔴 `bug` services/proxy/src/metrics.rs:30: COUNTERS array order does not match values() return order; sweep_bytes_reclaimed loads before sweep_blobs_removed so Prometheus labels them swapped
🔴 `bug` services/proxy/src/sweep.rs:98: sort_by_key(|candidate| candidate.age) sorts newest blobs first when over ceiling (age ascending = smallest age = newest), contrary to comment "Oldest first"
🔴 `bug` services/proxy/src/sweep.rs:140: clear_partials removes every file in incoming/ without checking if it is a partial write (pid-sequence temp file) rather than a 200 MiB artifact
🔴 `bug` services/proxy/src/routes/admin.rs:62: sweep calls app.sweeper.sweep(dry_run) directly instead of run() so the Mutex lock is bypassed and background sweep and admin sweep can race
🔴 `bug` services/proxy/src/sweep.rs:140 142: forget(&index, &gone) is executed even when dry_run=true, deleting index entries for digests that would never be removed
🔴 `bug` services/proxy/src/sweep.rs:40: collect uses fs::metadata (follows symlinks) instead of fs::symlink_metadata so the comment "A link is counted at the size of the link" is false for symlinks
🔴 `bug` services/proxy/src/sweep.rs:140 142: if fs::remove_file fails, removed/bytes counters and gone vec are still incremented and forget is called, leaving index entries for blobs that still exist 1
🔴 `bug` services/proxy/src/sweep.rs:185: age_of uses meta.modified() (mtime) instead of last-access time, so blobs fetched every hour but written 2 days ago get evicted despite CACHE_MIN_AGE and "package somebody fetched this morning stays" semantics
🔴 `bug performance` services/proxy/src/sweep.rs:90: sweep() and clear_partials run blocking fs calls on the async runtime without spawn_blocking, stalling the tokio thread pool for large stores
🔴 `bug` services/proxy/src/sweep.rs:102: when remaining == max_bytes the loop still removes blobs 1
🔴 `bug` services/proxy/src/main.rs:85: tokio::time::interval fires its first tick immediately (tokio default) so the first sweep happens right after startup instead of after one full interval as the comment claims 1
🔴 `bug` services/proxy/src/sweep.
Verifying the tokio interval first-tick behavior and the dry-run/`forget` path once more.
└ 3152 tok ·  53.5 tok/s · 43K ctx · 1114ms ttft · 58.9s wall
↳ search_files: search pr/services/proxy for interval_at|MissedTickBehavior|first tick
└ search_files: search complete
↳ read_file: read pr/services/proxy/src/sweep.rs
└ read_file: read complete
↳ read_file: read pr/docs/operations.md
└ read_file: read complete
-- reasoning --
I've found several concrete defects. Let me finalize the review with the ones I can point to specific lines for.
🔴 `bug` services/proxy/src/metrics.rs:50: COUNTERS array order (blobs_removed then bytes_reclaimed) mismatches values() return order (bytes_reclaimed then blobs_removed) at lines 94-95
🔴 `bug` services/proxy/src/sweep.rs:102: sort_by_key on 102 puts newest blobs first (smallest age) despite comment claiming oldest first
🔴 `bug` services/proxy/src/sweep.rs:140: forget() runs unconditionally after dry_run path, deleting index entries despite dry_run promise of "without removing anything"
🔴 `bug` services/proxy/src/routes/admin.rs: 76: admin::reclaim calls sweeper.sweep() bypassing running Mutex, violating one-at-a-time guarantee documented in sweep.rs
🔴 `bug` services/proxy/src/main.rs:108: tokio::time::interval first tick() fires immediately contradicting comment that first tick is one interval away
🔴 `bug ` services/proxy/src/sweep.rs:126: failed fs::remove_file still increments removed/bytes counters and calls forget(), corrupting metrics and index state
🔴 `bug` services/proxy/src/sweep.rs:160: fs::metadata() follows symlinks so size reported is target size, contradicting comment that links are counted at link size
🔴 `bug` services/proxy/src/sweep.rs:222: clear_partials() removes files from incoming while BlobWriter holds them open, killing active fetches
🔴 `bug` services/proxy/src/sweep.
🔴 `bug` services/proxy/src/sweep.rs:140: `forget` always deletes index entries after the candidate loop, including when `dry_run` is true, so `POST .../sweep?dry_run=true` still unlinks index files and breaks the “without removing anything” contract.
🔴 `bug` services/proxy/src/sweep.rs:102: `sort_by_key(|c| c.age)` orders ascending duration-since-mtime, so newest blobs are considered first; over-ceiling eviction deletes recent packages and keeps the oldest ones.
🟠 `bug` services/proxy/src/metrics.rs:94: `values()` emits `sweep_bytes_reclaimed` then `sweep_blobs_removed`, but `COUNTERS` names them in the opposite order, so Prometheus scrapes swap blob-count and byte-total.
🟠 `bug` services/proxy/src/sweep.rs:224: `clear_partials` unlinks every file under `incoming`, including live `BlobWriter` temps still being fetched, so an in-flight miss can lose its temp mid-write.
🟠 `bug` services/proxy/src/routes/admin.rs:76: the admin path calls `sweeper.sweep` and never takes `running`, so it can run concurrently with `run()` and double-count/over-delete against the one-sweep-at-a-time guarantee.
🟠 `bug` services/proxy/src/sweep.rs:90: `sweep` does blocking recursive FS I/O on the async worker (via `run` and the admin handler) with no `spawn_blocking`, so a large store stalls the proxy event loop.
🟡 `bug` services/proxy/src/main.rs:115: `tokio::time::interval` fires its first tick immediately, so the process sweeps on startup despite the comment that the first pass waits one full interval.
🟡 `bug` services/proxy/src/sweep.rs:126: a failed `remove_file` still increments `removed`/`bytes` and adds the digest to `gone`, so metrics over-report and `forget` drops index entries for blobs that are still on disk.
🟡 `bug` services/proxy/src/sweep.rs:185: eviction age uses `modified()` only; cache hits never refresh mtime, so frequently served old blobs look cold and are preferred for removal once the store is over ceiling.
└ 2161 tok ·  52.2 tok/s · 45K ctx · 1175ms ttft · 41.4s wall