2021-12-22 QA in Staging seeing high rate of HTTP429s
Current Status
Staging QA tests failing due to rate-limiting. After reverting gitlab-org/gitlab!76965 (merged) tests seem to be reliably passing again.
QA tests handle rate-limiting gracefully but only to a certain extent. If we start backing off and waiting too often, the job will time out as we saw in this incident.
Timeline
Recent Events (available internally only):
- Deployments
- Feature Flag Changes
- Infrastructure Configurations
- GCP Events (e.g. host failure)
All times UTC.
2021-12-22
-
16:16
- QA show's signs of failing due to rate limiting: https://ops.gitlab.net/gitlab-org/quality/staging/-/pipelines/952000 -
17:06
- Quality team is engaged -
17:29
- Suspect rate limiting avoidance mechanism is not working -
17:49
- Issue persist after later deploy: https://ops.gitlab.net/gitlab-org/quality/staging/-/pipelines/952114 -
17:49
- Quality Engineers bumps rate limits:- Maximum authenticated web requests per rate limit period per user - 1000 -> 2000
- Maximum authenticated API requests per rate limit period per user - 1000 -> 2000
-
18:32
- All known running QA pipelines against staging are cancelled -
18:33
- Latest auto-deploy QA pipeline is retried: https://ops.gitlab.net/gitlab-org/quality/staging/-/pipelines/952114 -
19:45
- Attempted mitigation via feature: https://docs.gitlab.com/ee/user/admin_area/settings/user_and_ip_rate_limits.html#use-an-http-header-to-bypass-rate-limiting -
19:46
- Latest QA pipeline is retried -
21:01
- QA continues to fail -
21:06
- Logs nonprod-log.gitlab.net appear to show that a large number of the requests without the"throttle_safelist":"throttle_bypass_header"
are on the/-/issues/new:
endpoint. -
21:46
- gitlab-org/gitlab!76965 (merged) is identified as possible root cause #6108 (comment 793186307). A revert MR is opened -
23:12
- Revert MR is merged
2021-12-23
-
02:20
- Coordinated pipeline with revert MR starts deploy to staging https://ops.gitlab.net/gitlab-org/release/tools/-/pipelines/952566 -
03:03
- QA on staging finishes successfully https://ops.gitlab.net/gitlab-org/quality/staging/-/pipelines/952819
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