<will...@25thandclement.com> wrote: > On Sat, May 02, 2009 at 09:33:14PM -0700, Dan Kegel wrote: >> Fwiw, with edge-triggered mode, you don't need to do any such futzing. > > How's that?
With edge-triggered mode, your app is sent notifications only when the readiness state of an fd *changes*. That means you never have to tell the OS when your interest mask changes, as you manage that yourself in userspace. It saves a fair number of syscalls. This doesn't matter unless you're trying to really get close to hardware performance. It's also kind of a large rethink for most folks used to select() or poll(); your app's state machine has to handle readiness notifications without fail in edge-triggered mode. If your state machine isn't airtight, connections will seem to hang. But for me it was worth the extra effort in programming, and after I got used to it, it was simpler than the traditional way. Not all OS's support edge-triggered mode, but IIRC Linux, BSD, and Solaris do. I haven't tried it with libevent yet, but I hear tell that 2.0 has support for it. - Dan _______________________________________________ Libevent-users mailing list Libevent-users@monkey.org http://monkeymail.org/mailman/listinfo/libevent-users
