Discarding old VCL

[Michael Lenaghan]

> The idle worker threads hold a reference to the last VCL they used
> when they sleep, so until you have exercised all your threads during
> peak-load, you may have old VCL's linger around.
>
> Not optimal obviously, but you would have to load a lot of VCL's
> for it to become a problem.

Ah, thanks for the explanation. It helps to understand the model. And
the model is certainly good enough for us; my only concern was a very
slow resource leak.