Code RoomShared dependency saturates on surge
HardPrep Room Coding #2856

Shared dependency saturates on surge

On-callDistributed systemsCode quality & reviewSenior–Staff~30 min

A big live event drives a 6x surge to your video-start API. That service autoscales fine and stays healthy, but starts failing because a shared `entitlement` service it calls (also used by 9 other teams) saturates: the entitlement service's DB connection pool is exhausted and it returns 503s, which cascade into your video-starts AND degrade the 9 unrelated teams. Your service is already correctly caching entitlements for 60s. How do you triage and mitigate, balancing your incident against the shared-dependency blast radius?

What a strong answer looks like

Stop the bleeding first (mitigate), then form hypotheses from real signals. Separate root cause from symptom, communicate status as you go, and close with what prevents a repeat.

0:00 of about 30 min
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