I'm currently working on an XP 32 bit system with AMD Athlon 64 3200+
CorelDraw is displaying a print preview but is otherwise completely idle. It has finished displaying the preview, so it is just waiting for user action but has nothing else to do.
Photopaint in another window was running extruciatingly slow so I checked task manager. CorelDraw.exe was showing to be using 98% of the CPU.
On further investigation, this happens only when the print preview is on the screen. I close the print preview, return to CorelDraw design screen and CPU is 0% when idle. I do another print preview -- 98% CPU again.
I'll try it later on a quad core system, but it seems that print preview should not be hogging the CPU when idle waiting for operator action.
Hello harry; Does the computer have a separate video card?
George
It does. Nvidia GeForce 6200.
But this looks more like software forgetting to include a sleeping or task switching statement in its "waiting for a keystroke" loop.
I might understand if the CPU was doing the video, but with a video card I wouldn't have thought it would tie up that much of the CPU.
harry on a i5 with 8 gb ram and a 2 gb Nvidia 550, an print preview it is using 25% of the CPU with no more use of ram than when it's closed?
It's a common mistake when programming for windows. When software has nothing to do, it must tell windows that it has nothing to do (typically by requesting to sleep for 0.1 sec) so that windows can allocate the time to another process that can actually use the time.
0.1 seconds may sound quite short, sound a lot, but the CPU can actually do rather a lot with it -- especially as the original process probably still doesn't have anything to do afterwards. So it can sleep over and over again for possibly quite a large number of 0.1 second periods until the user actually does something. At this point it should normally get the CPU back within 0.1 sec. provided that there's not some other program on the system that is forgetting to sleep when idle.