Replit
database
HikariCP Connection Pool Misconfigured
Connection pool errors or timeout exceptions appear in logs. HikariCP is misconfigured for Replit's resource constraints.
Connection pool size, timeout, and idle settings must match Replit's limited database connections.
Error Messages You Might See
HikariPool - Connection is not available, request timed out
HikariPool - Failed to validate connection
Connection pool error
Common Causes
- Pool size too large (default 10, Replit max ~20)
- Connection timeout too short
- Idle timeout not set, keeping stale connections
- LeakDetectionThreshold set too low
- No auto-increment pool size for traffic spikes
How to Fix It
Set spring.datasource.hikari.maximum-pool-size=8, spring.datasource.hikari.minimum-idle=2. Configure spring.datasource.hikari.connection-timeout=20000ms. Set spring.datasource.hikari.idle-timeout=300000ms. Monitor pool usage in logs and adjust based on traffic patterns.
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Get HelpFrequently Asked Questions
What's a good pool size for Replit?
Start with 8 maximum and 2 minimum. Adjust based on concurrent user load
What if I still get timeout errors?
Increase connection-timeout or check for connection leaks in your code