I notice now that in the doco cleanup before pool 1.5, we left one more inscrutable "feature" of GKOP undocumented, namely the behavior determined by the clearOldest method added in pool 1.3. This (non-optional) feature destroys 15% of the "oldest" idle instances in the union of the pools to "make room" when a borrowObject attempt bumps up against maxTotal and there are idle instances (with other keys) that could be sacrificed. This behavior makes sense for the DBCP use case (prepared statement pools), but may not always be desirable. I think it should be configurable (whether or not to do it and possibly the trimming %) and documented. The 1.5 changes to take factory methods out of synch blocks also increase the activation rate of clearOldest, since the internal processing count is included in the guard. It might actually be better to eliminate that from a performance perspective (i.e. only activate when _totalActive + _totalIdle >= _maxTotal).
This feature was implemented in POOL-49. Prior versions just invoked clear() to eliminate all idle instances when maxTotal was attained. Phil
