# X_DB_POOL_EXHAUSTED

## Means

no connection was available

## Typical cause

SQLSTATE `53300` from the server, or the local pool answering nothing inside `acquireTimeoutMs`, for a plain statement as for a transaction (`As of 2026-11-02`) — deliberately one code, because to a caller both mean "there was no connection for this unit of work" and a second code would split one runbook in two. Refused rather than queued forever: a hang makes `/readyz` join the queue, the kubelet kills the pod, and the next pod inherits the same saturated database

## Fix

set `DATABASE_POOL_MAX` below `max_connections / replicas` (per-role default: `POOL_PROFILES`), or cut the replica count

[Entity and database](/error-codes#entity-and-database)