On Wed, May 30, 2007 at 09:21:36PM -0700, Bryan O'Sullivan wrote:
I notice that select is a bit of a bottleneck in the non-threaded RTS once lots of sockets are in play. Between kernel and userspace, many a cycle are wasted once we go past a few hundred clients. On some operating systems, the fixed nature of fd_set imposes a surprisingly low ceiling on the maximum number of concurrently open file descriptors.
I gather there's some kind of longish-term plan to build a more pluggable RTS, but it seems like a nearer-term solution could be implemented relatively cheaply, and wouldn't conflict with the ultimate goal.
Would the GHC team be interested in receiving a patch that replaced select, where possible, with an operating system's native, and hopefully faster, event wait mechanism?
I don't beleive the GHC team would be interested in receiving any patches to the non-threaded RTS, since it is scheduled for removal in 6.8 IIRC (leaving only threaded). Stefan