Agents panel: omarchy-agent-usage-codex re-parses every Codex session file on each refresh (55s CPU per cycle)

[EY3G0R3]

What happens

On every agents-panel refresh, omarchy-agent-usage-codex re-parses every
~/.codex/sessions/**/*.jsonl file modified in the last 30 days, from scratch.
With a normal amount of Codex history this turns into a recurring, visible CPU
spike — omarchy-agent-u* sitting at 100% of a core for about a minute, every
15 minutes, indefinitely.

Measured on this machine (AMD Ryzen AI 9 HX PRO 370, 24 threads, Python 3.14.7):

	files in 30-day window	wall	user CPU
omarchy-agent-usage-codex --force	1468 files / 7.8 GB	56.9 s	54.8 s
omarchy-agent-usage-claude --force	919 files / 440 MB	~2 s	~2 s

99% CPU-bound, not I/O-bound.

What I expected

A periodic stats refresh that costs roughly nothing, because Codex session
files that belong to finished sessions never change again.

Why it is this expensive

Two things, one cheap to fix and one structural.

1. No pre-filter before json.loads. The Claude collector skips any line
that cannot be relevant before parsing it
(bin/omarchy-agent-usage-claude, in scan_project_transcripts):

# Cheap pre-filter before JSON parsing keeps files with unrelated
# lines inexpensive.
if '"usage":' not in line:
    continue

The Codex collector has no equivalent — scan_native_codex_sessions in
bin/omarchy-agent-usage-codex calls json.loads(raw) on every line of every
file, then discards everything whose payload type is not token_count.
Those lines are a small minority of a session transcript.

Adding the matching guard:

for raw in handle:
    if '"token_count"' not in raw and '"turn_context"' not in raw:
        continue
    try:
        entry = json.loads(raw)

takes the same run from 54.8 s to 20.9 s of user CPU (56.9 s → 22.6 s wall),
with byte-identical output — I diffed todayPrompts, todaySessions,
todayTotalTokens, totalPrompts, totalSessions, activeDays,
modelUsage, recentDays and todayTokensByModel between patched and
unpatched runs and they match.

2. The cache is whole-result and time-bounded, so every refresh is a full
rescan. SCAN_REUSE_SECONDS = 20 exists only to dedup concurrent collector
runs, as its comment says:

# every periodic widget refresh lands a real rescan, however low
# refreshIntervalSec is set.

So even with the pre-filter it is still ~21 s of CPU every
refreshIntervalSec (default 900, shell/plugins/agents/Main.qml). Because a
closed session file is immutable, a per-file cache keyed on
(path, st_mtime, st_size) -> per-day/per-model totals would make steady-state
refreshes proportional to what actually changed — usually one live session —
instead of to the whole 30-day window. The existing
scan_cache_paths() / _cached_local_stats() machinery looks like the natural
place for it.

The pre-filter alone is a worthwhile standalone fix; the per-file cache is what
makes the cost stop scaling with accumulated history.

Steps to reproduce

1. Accumulate Codex sessions until ~/.codex/sessions holds a few GB inside a
   30-day window (du -sh ~/.codex/sessions).
2. time omarchy-agent-usage-codex --force >/dev/null
3. Compare with time omarchy-agent-usage-claude --force >/dev/null, which
   scans a comparable file count with the pre-filter in place.
4. Leave the agents panel enabled and watch omarchy-agent-u* in top at each
   refreshIntervalSec boundary.

System

• omarchy version: 4.0.4-1
• Kernel: 7.2.5-3-omarchy
• Python: 3.14.7
• CPU: AMD Ryzen AI 9 HX PRO 370 (24 threads)

Workaround, for anyone who lands here first

Move older Codex transcripts out of the scanned roots — note that both
sessions and archived_sessions are scanned, so the destination has to be
neither:

mkdir -p ~/.codex/sessions-old
find ~/.codex/sessions -name '*.jsonl' -mtime +3 -exec mv -t ~/.codex/sessions-old {} +

Or make the spike rarer without making it smaller:

omarchy bar set omarchy.agents refreshIntervalSec 3600 --json

Disabling the Codex provider in shell.json does not help:
providerEnabled() only gates display, and omarchy-agent-usage-update still
forks every collector.

---

Filed by Claude Opus 5 via Claude Code.

[omarchybot]

Fixed on quattro by #14049. The native Codex scanner now prefilters relevant records and caches per-file totals, reusing unchanged rollouts rather than parsing the whole history each refresh. This incorporates #12803 and #12595. Changed files are still read in full; append-only optimization remains separate work in #12336.

Closing as completed. If the same failure persists after updating to a build containing the fix, please reopen with the collector output.

Closure scope checked by GPT-6 in Codex and Codex Medium against the reports and landed source. The second opinion agreed; independence is not guaranteed. No runtime tests were rerun for this reconciliation.