Sent from my iPhone
> On Aug 22, 2018, at 10:40, Alastair Houghton <alast...@alastairs-place.net> > wrote: > >> On 22 Aug 2018, at 17:53, Jens Alfke <j...@mooseyard.com> wrote: >> >>> On Aug 21, 2018, at 8:33 AM, Alastair Houghton >>> <alast...@alastairs-place.net <mailto:alast...@alastairs-place.net>> wrote: >>> >>> So, for instance, it’s not so good on macOS or iOS if its event dispatcher >>> is based on select(), (e)poll() or kqueue() because what you really want on >>> macOS/iOS is for the event dispatch to go via CFRunLoop; if it doesn’t, >>> you’ll end up having to use threading to run the network library’s event >>> loops on background threads, which for an async networking library kind of >>> defeats the point IMO. >> >> It does mean you have to spin up one background thread to sit and wait for >> events; but that's not a big hardship. You still get the scalability >> benefits of event-driven I/O, vs. having to use one thread per socket the >> old-fashioned way. > > Well, yes and no. If the network library works that way, it’ll fire its > callbacks on the background thread, which makes life awkward if you’re > interacting with the UI as you’ll need to forward to the main thread and it > may in some cases for you to use synchronisation when you wouldn’t have > needed to. Much better to use a library that’s properly integrated with the > native run loop and that therefore doesn’t end up calling your code on a > background thread. > >> (NSURLSession and Network.framework are doing the same thing under the hood, >> after all.) > > Are they? kqueue() supports monitoring of fds, Mach ports and timers, so > there’s really no reason that CFRunLoop would have to spawn a background > thread just to monitor some file descriptors. As far as I can tell, the > current CFRunLoop implementation is built on top of GCD, which sadly we don’t > have the source code for libdispatch is open source: https://github.com/apple/swift-corelibs-libdispatch > ; I don’t have time to reverse engineer it right now to see whether or not > GCD does in fact spawn background thread(s) for this or not, but I see no > particular reason it should have to. > > Kind regards, > > Alastair. > > -- > http://alastairs-place.net > > _______________________________________________ > > Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) > > Please do not post admin requests or moderator comments to the list. > Contact the moderators at cocoa-dev-admins(at)lists.apple.com > > Help/Unsubscribe/Update your Subscription: > https://lists.apple.com/mailman/options/cocoa-dev/saagar%40saagarjha.com > > This email sent to saa...@saagarjha.com _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
