CLIENT PAUSE ALL for the length of the chaos phase instead of CLIENT PAUSE WRITE, so every Redis touchpoint on the request path times out rather than just the writes. The pause is sized to the phase because it freezes the control connection too; teardown's CLIENT UNPAUSE is a safety net for a phase that overran
Latency, RSS and CPU are now budgeted as chaos-over-baseline ratios (p50/p90/p99 for latency and RSS, CPU seconds per request once) through a small phase_budget module, replacing the machine-shaped absolutes. The Redis timeout rate is reported but no longer asserted
The final /metrics scrape waits for litellm_deployment_failure_responses_total to stop moving, since that counter is bumped from the async logging queue and lagged the load generator by thousands of increments. The model group carries a unique marker so a deployment left behind by an aborted run cannot absorb this run's retries
Co-Authored-By: Claude Code <noreply@anthropic.com>
The sequential version sent one request at a time, so a Redis outage never
reached the concurrency where the failed-tracking alert body actually grows.
This drives the proxy with locust against one model group of three mock
deployments, two failing at order 1 and one serving at order 2, so every
request spends its retries on the failing pair and lands on the serving
deployment through the order-based fallback. Two phases, a healthy baseline
and a CLIENT PAUSE WRITE window, and every request must succeed in both.
Latency, RSS and CPU are reported as p50/p90/p99 per phase rather than
asserted on: RSS and CPU come from psutil on the proxy's process tree, since
a multi-worker proxy serves /metrics from the prometheus multiprocess
collector and that drops the process collector's series. Thresholds stay open
until weekly runs give real baselines.
Co-Authored-By: Claude Code <noreply@anthropic.com>