empty pool issues

[Danny Faught]

I'm looking for a solution for one of our customers for the empty pool problem that leads to timeout errors (like issue #1474 and probably others).

I'm curious about this item in the CHANGES file:

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Changes in 5.0.0

* rewrote connection elide/add code to fix an unconfirmed but occassionally reported race condition that results in the pool draining to 0 and not refilling.

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Can anyone point to the commit that this is referring to?

I'm also curious what changed in 5.0.1, and also with the commits in the last year that aren't released yet.

Thanks,

Danny