Hi Carsten, The control application has custom keyboard device, basically it's a PS/2 keyboard that only has special key need for it's operation. My problem is in certain condition, the application respond to the keyboard's key pressing-event is unpredictable, sometime it was late to caught the event for about 0.5 - 1 second, the application does not consume a lot of CPU time, it just wait for the pressed key. I think this a normal X behaviour. Ardhan --- Carsten.Emde@xxxxxxxxx wrote: From: Carsten Emde <Carsten.Emde@xxxxxxxxx> To: Ardhan Madras <ajhwb@xxxxxxxx> CC: RT-Users <linux-rt-users@xxxxxxxxxxxxxxx> Subject: Re: PREEMPT_RT on X/GTK+ Date: Sat, 28 Nov 2009 14:23:56 +0100 Ardhan, > Is there special care when using PREEMPT_RT patch in X/GTK+ > applications? [..] In general, no other care than with any other RT application. Do you wish the GUI to immediately and smoothly reflect important states of your control application? In this case, you should consider that the display only changes, if both the GTK+ application and the X server react in time. For this purpose, it is sometimes recommended to set the priority of the X server a little less than that of the control application. Never assign the highest priority of the system to the X server, since this may completely block the server. A priority of < 49, however, is normally safe. Carsten. -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html _____________________________________________________________ Listen to KNAC, Hit the Home page and Tune In Live! ---> http://www.knac.com -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html