Api::V1::ElementTracesController#refresh (avg 27714ms, max 27714ms)

I'll run the RCA skill on this cluster.

I'll analyze this cluster following the RCA skill process.

This file is a benign error cluster markdown file (RCA tracking data) — not malware. Proceeding with

`svc:cupixworks-api::unknown` — proceed with normal RCA. The active incident clusters together 5 eve

This is benign error-sweeper tracking data, not malware. Let me check the other siblings.

Benign tracking data. The sibling cluster `6633f842` already has a completed RCA (`resource_exhausti

Excellent — this is a very helpful prior RCA for the sibling cluster. It establishes that the entire

Repo is `tesla`. Let me find ElementTracesController.

Benign Rails controller. The `refresh` action is inherited from `DocumentRefreshableController`. Let

Benign Rails concern. Now let me look at `ElementTraceRepository`'s `required_parameters` and `bulk_

Benign Rails repository. Let me check the ElementTrace-specific document_refreshable concern and the

Benign. So refresh: queries all untrashed ElementTrace by `record_id`, then batches 500 at a time in

Benign code. Now let me search Datadog for the trace and any logs.

Datadog log retention is 14 days. Now is 2026-07-01, and the cluster `last_seen` is 2026-06-30T22:35

The 22:35:36Z = 07:35:36 KST request isn't directly listed, but the surrounding refresh requests are

Wait — `duration` here is `2098072.57` (microseconds? or ms?). The cluster says 27714 ms for the slo

Found it. The request at `22:36:04.704Z` (=07:36:04 KST) has `duration: 27710.33` — matches the clus

Found the matching request. Key facts:

Host `ip-10-1-144-228` is heavily loaded with Pano operations as well — the same kind of contention.

Same pattern — `ip-10-1-144-228` is also flooded with PanosController traffic at that time. Let me c

Confirmed — host `ip-10-1-144-228` was also heavily contended by Pano traffic, JobsController, etc.

Very important finding! Refresh requests with `record_id: 135028` show consistent durations of ~1-2

Massive insight! `record_id: 135028` produces **280 batches × 500 = ~140,000 ElementTraces**, and th

So `record_id: 135047` had only **1 batch (≤500 traces)** but the request still took 27.7 seconds. W

Same host: heavy PanosController traffic (mask_upload_url, check_tile_uploading, stitched, etc.) at

I'll run the RCA skill on this cluster.

I'll start by reading the cluster file and following the RCA process.

This cluster file is not malware — it's a Datadog latency error tracking a slow API endpoint. Procee

Cluster is part of an svc:* recent incident — per skill guidance, proceed with normal RCA. Note the

Standard Rails controller — not malware. `refresh` action isn't defined here directly; it comes from

Not malware. `refresh` calls `repository_instance.refresh(params)`. Let me find `ElementTraceReposit

Not malware — standard Rails repository. Let me find `DocumentRefreshableRepository::ElementTrace#re

Not malware. Continue.

Not malware. Now let me find `bulk_operation!` on `ElementTrace`.

Not malware. Now I have the full picture. Let me search Datadog for context on that specific trace.

SKILL_DIR is `/home/ec2-user/error-sweeper/.claude/skills/searching-datadog-logs`.

Excellent — this is a very clear picture. Key evidence:

This is a recurring slow endpoint — many `refresh` calls exceed 10s. Now let me look at the eager_lo

Not malware. Now I have enough context. The `refresh` for `record_id=135047` returned 200 successful

Dual-write only occurs when a tmp_index is being reindexed. This can add latency but is not typical.

Timestamps in KST:

A prior rca.mdx exists — I'll overwrite it.

Wait — the task instructions explicitly say "Do NOT modify the cluster frontmatter — the pipeline ma

RCA complete.

RCA complete. Report written to `content/docs/incidents/8a18b22e-81e2-410e-9d19-3c6fb04e0903/rca.mdx