feat(load_test): add optional per-user x-session-affinity#127
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Add --per-user-session-affinity so each Locust user gets a stable, distinct x-session-affinity header. This spreads concurrent load across session-affinity routes instead of collapsing serverless traffic onto a single account-level session.
Use --session-affinity-prefix or LOAD_TEST_RUN_ID/RUN_ID/GITHUB_RUN_ID so
session ids are scoped to a workflow run ({prefix}-user-N) instead of only
the locust process pid.
Generate one random run suffix per load test and assign user-0_<id>, user-1_<id>, ... Optional prefix/env still overrides the suffix for GHA.
Each user generates a uuid in on_start and reuses it as x-session-affinity for the whole run. Drop run-scoped prefix machinery.
![cursor[bot]](https://avatars.githubusercontent.com/in/1210556?s=60&v=4){kind=small}
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Risk: low. Approved: optional --per-user-session-affinity is off by default, scoped to llm_bench load testing only, and matches the stated intent. Cursor Bugbot passed with no findings; Cursor Security Agent was not configured on this PR. No reviewers assigned.
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nlsnln
approved these changes
Jul 4, 2026
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Note
Low Risk
Benchmark-only client header behavior in llm_bench; no production inference or auth paths change.
Overview
Adds
--per-user-session-affinity(off by default) so each Locust virtual user gets a stable randomx-session-affinityvalue for all of its requests, which helps load tests hit multiple session-affinity / prompt-cache routes instead of collapsing onto one sticky session.When enabled, the id is created in
on_startviauuid.uuid4().hexand applied after--headerprocessing, so it overrides anyx-session-affinityset through--header. The README documents when to use this for Envoy stickiness and concurrent-user benchmarks.Reviewed by Cursor Bugbot for commit d45ce93. Bugbot is set up for automated code reviews on this repo. Configure here.