Increase pool stacks to 32

[fbryden]

No description provided.

[BurntSushi]

A change like this without literally any accompanying explanation or benchmarks isn't really appropriate. The obvious downside of this change is that it increases memory usage across the board. In particular, that CacheLine is problematic since it takes up 64 bytes on its own. So this change increases base memory usage from 8 * 64 = 512 bytes to 32 * 64 = 2,048 bytes.

[fbryden]

@BurntSushi I am so so sorry, I did not mean to open this pull request against the original repo - it was only meant for my fork. I completely understand (and agree) this change is not appropriate across the board!

[BurntSushi]

Ah no worries, understood.

(I might be open to making this a runtime configurable parameter. If you want to file an issue about it.)

[fbryden]

Thank you so much!
I've filed #1241