I've experienced weird connection pool issue in 4.0.9 these days.
After every hour (exactly), the 4.0.9 resin refused to service any
request and occasionally report "ConnectionPool [...] pool overflow".
This situation never occurred in prior resin releases and neither my
webapp nor config was not modified at all after upgrade 4.0.5 to
I've no idea what happened though I research the 4.0.9 source code.
I noticed that ConnectionPool.java & UserPoolItem.java were moved to
another package but no major modification were made.
I did a fine log, here goes the log content (partial) for download:
Resin database config:
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