On Saturday 10 July 2004 00:50, William wrote: > I'm not familiar with the internals of KDE. How efficient is KDE's DCOP > IPC compared to Linux IPC? I know it's not relevant to the refresh > problem, given what you say below. Here you can read a good detailed introduction about it: http://developer.kde.org/documentation/library/kdeqt/dcop.html
> Is there any reason why the timer frequency could not be changed > dynamically depending on whether or not the Studio window is actually open, Remember that the timer is running as part of the sequencer process, and the Studio window belongs to the GUI. Of course, you can send messages from the GUI to the sequencer when the Studio window is opened and closed. > > when some record device returns to the system, and it is > > remembered to be connected some time ago. In this case, the device > > manager will try to subscribe it as an input port, and this triggers > > more refreshes. > Why would subscribing it as an input port trigger more than one refresh? Because there are two roundtrips involved: first, when the new device is discovered, and second when the GUI realizes that our new device should be subscribed to the input port. > Is there an upper limit on the length of the "very short time period" > during which the different announce messages from executing a single > new ALSA program are all delivered? Could that uppper limit plus a > small safety-margin be used as the timer frequency? > Would a group of related announce messages following a single new ALSA > program execution ever come close to having a 3 seconds gap between any of > the messages? Is that why the timer has a period of 3 seconds? No, there is not any limit. It depends absolutely on the clients. The messages are broadcasted as a result of some ALSA API functions executed at program startup (or elsewhere). When you successfully call to snd_seq_open(), ALSA sends an announcement welcoming a new client on the system. If you call snd_seq_create_simple_port() and friends, ALSA sends a "new port arrived" message. When each client, port or subscription is successfully attached, detached or modified, ALSA generates an announcement. Some function calls are usually grouped on each ALSA program startup and exit. vkeybd generates two announces, usually in less than 5 milliseconds (in my system) at startup, exit, and when you use it's file/connection command. qjackctl generates three messages on startup in a span of 15 ms. qsynth generates only two, in less than 10 ms. You can, of course, start some programs sequentially with a script. In that case the messages for the whole script can fit in a span of several seconds. Regards, Pedro ------------------------------------------------------- This SF.Net email sponsored by Black Hat Briefings & Training. Attend Black Hat Briefings & Training, Las Vegas July 24-29 - digital self defense, top technical experts, no vendor pitches, unmatched networking opportunities. Visit www.blackhat.com _______________________________________________ Rosegarden-devel mailing list [EMAIL PROTECTED] - use the link below to unsubscribe https://lists.sourceforge.net/lists/listinfo/rosegarden-devel
