> On Wed, 2019-12-04 at 18:24 +0800, cheng...@emindsoft.com.cn wrote: >> From: Chen Gang <cheng...@emindsoft.com.cn> >> >> The global (un)lock xserver operations will have effect to the whole >> system, and all the other gui apps have to be blocked, so the operations >> should not be buffered, or may cause sync issue, e.g. reboot machine. > > Enh. I can maybe see the point of this for XUngrabServer, but I think > doing this for XGrabServer may actually make interactivity worse. With > the code as it is currently, the GrabServer request will be buffered > inside the client until something happens to flush it out (presumably > something like QueryTree or GetImage that provokes a reply), and while > it stays buffered other clients may still interact with the server. > With this change you'll immediately write the request to the server, > and you might lose your scheduler timeslice as a result, in which case > not only will the grabbing client need to wait to reschedule but every > other client will need to wait in line behind the grabbing client. >
Oh, for me, what you said is reasonable. I got the issue because the XUngrabServer did not call _XFlush() immediately. _XFlush for XGrabServer is not necesscary for my current issue, either not good for the performance. Originally, I felt XGrabServer and XUngrabServer were a pair, and I was not quite sure enought. So I used _XFlush for both of them (it must be safe enough, altough it has negative effect with the performance). > Do you have a scenario in mind that this helps with? Does doing _XFlush > only for XUngrabServer work just as well? > At least for me, _XFlush only for XUngrabServer should be work well. Welcome you to apply the patch with the new modification (only _XFlush for UngrabServer). By the way, I can not join in xorg-devel@lists.x.org mailing list. I tried, but got "No ReCAPTCHA response provided". Welcome any ideas about it. Thanks. _______________________________________________ xorg-devel@lists.x.org: X.Org development Archives: http://lists.x.org/archives/xorg-devel Info: https://lists.x.org/mailman/listinfo/xorg-devel
