On 15.12 17:14, John Meacham wrote:
On Thu, Dec 15, 2005 at 02:02:02PM -0000, Simon Marlow wrote:
With 2k connections the overhead of select() is going to start to be a problem. You would notice the system time going up. -threaded may help with this, because it calls select() less often.
we should be using /dev/poll on systems that support it. it cuts down on the overhead a whole lot. 'poll(2)' is also mostly portable and usually better than select since there is no arbitrary file descriptor limit and it doesn't have to traverse the whole bitset. a few #ifdefs should let us choose the optimum one available on any given system.
To matters nontrivial all the *nix variants use a different more efficient replacement for poll. Solaris has /dev/poll *BSD (and OS X) has kqueue Linux has epoll Also on linux NPTL+blocking calls can actually be very fast with a suitable scenario. An additional problem is that these mechanisms depend on the version of the kernel running on the machine... Thus e.g. not all linux machines will have epoll. - Einar Karttunen