This is done once (OS X 10.10.5): commonSendQueue = dispatch_queue_create( “common socket queue", DISPATCH_QUEUE_SERIAL);
Several objects do this quite often: NSDate *dax0 = [ NSDate date ]; dispatch_async(commonSendQueue, ^{ @autoreleasepool { [ someOtherObject doSomethingwithDate: dax0]; }}); double delay1 = 50 msec NSDate *dax1 = [ NSDate dateWithTimeInterval: delay1 sinceDate: dax0 ]; dispatch_time_t disTim1 = dispatch_time(DISPATCH_TIME_NOW, (int64_t)( delay1 * NSEC_PER_SEC)); dispatch_after(disTim1, commonSendQueue, ^{ @autoreleasepool { [ someOtherObject doSomethingwithDate: dax1]; }}); someOtherObject does: - (void) doSomethingwithDate: (NSDate *)date { NSTimeInterval inDelay = -date.timeIntervalSinceNow * 1e3; if ( inDelay > 12 ) NSLog(@"%s in-delay %9.3f msec",__FUNCTION__, inDelay); } The in-delay is usually less than a dozen milliseconds. But in the call with dispatch_after (never with dispatch_async) the in-daly is sometimes is 10 seconds - sometimes even 20 or 30 seconds - mostly (but not always) near an integral multiple of 10 seconds. Why this delay of 10 seconds, and how can I find out, what is the cause of it? A breakpoint in doSomethingwithDate shows: * thread #12: tid = 0x341eb, 0x0000000100012a43 gLifx`-[GCDAsyncUdpSocket doSomethingwithDate:](self=0x00006180001e7300, _cmd=“ doSomethingwithDate:", date=2016-03-30 06:34:00 UTC) + 179 at GCDAsyncUdpSocket.m:1851, queue = 'common socket queue', stop reason = breakpoint 1.1 — * frame #0: 0x0000000100012a43 gLifx`-[GCDAsyncUdpSocket doSomethingwithDate:](self=0x00006180001e7300, _cmd="doSomethingwithDate:", date=2016-03-30 06:34:00 UTC) + 179 at GCDAsyncUdpSocket.m:1851 frame #1: 0x00000001000830ea gLifx`__52-[LFXUDPGatewayConnection sendNextMessageFromOutbox]_block_invoke186(.block_descriptor=0x00006000000852d0) + 138 at LFXUDPGatewayConnection.m:359 frame #2: 0x000000010018c989 libdispatch.dylib`_dispatch_call_block_and_release + 12 frame #3: 0x0000000100187fc3 libdispatch.dylib`_dispatch_client_callout + 8 frame #4: 0x000000010019cd40 libdispatch.dylib`_dispatch_after_timer_callback + 322 frame #5: 0x0000000100187fc3 libdispatch.dylib`_dispatch_client_callout + 8 frame #6: 0x0000000100196b20 libdispatch.dylib`_dispatch_source_latch_and_call + 1239 frame #7: 0x000000010018df1c libdispatch.dylib`_dispatch_source_invoke + 425 frame #8: 0x000000010018c471 libdispatch.dylib`_dispatch_queue_drain + 1002 frame #9: 0x000000010018bf28 libdispatch.dylib`_dispatch_queue_invoke + 223 frame #10: 0x000000010018b9de libdispatch.dylib`_dispatch_root_queue_drain + 666 frame #11: 0x000000010018b73c libdispatch.dylib`_dispatch_worker_thread3 + 106 frame #12: 0x00007fff91241a9d libsystem_pthread.dylib`_pthread_wqthread + 729 frame #13: 0x00007fff9123f3dd libsystem_pthread.dylib`start_wqthread + 13 (lldb) Gerriet. P.S. instead of dispatch_after I tried NSTimer and nanosleep. Same problem. I also removed the autorelasepool - made no difference. _______________________________________________ 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