Question

It's 14:10 and you're on call for the payments API (Java/Spring Boot, Postgres via HikariCP, behind an ALB). PagerDuty fires: p99 latency on POST /charges jumped from 180ms to 2.4s, while p50 is unchanged at 60ms. Error rate is flat — nothing is failing, requests are just slow. The Hikari dashboard shows `connections.active` pinned at the pool max of 20 and `connections.pending` climbing into the dozens. Postgres `pg_stat_activity` shows ~20 sessions, most in state `idle in transaction`. A deploy went out at 13:55 that 'added an external fraud-score lookup before committing the charge.' Walk me through how you triage this and what you do in the next 15 minutes versus the next week.