Like Antoine, I'm really skeptical about the backport: honestly, this change doesn't bring much in a normal application. To run into the number of open file descriptors limit (so the "scalability" aspect), one would need to have *many* concurrent threads reading from /dev/urandom. For the "performance" aspect, I have a hard time believing that the overhead of the extra open() + close() syscalls is significant in a realistic workload. If reading from /dev/urandom becomes a bottleneck, this means that you're depleting your entropy pool anyway, so you're in for some potential trouble...

> There is a reason we don't backport new features!

Couldn't agree more. This whole "let's backport security enhancements" sounds scary to me.