CPU gets maxed when menus are open.

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Amiganaut
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Joined: Fri Jul 24, 2009 2:44 pm

CPU gets maxed when menus are open.

Post by Amiganaut »

I notice that when I use Sheepshaver in OS X (10.6.8) that whenever I open a menu in the emulated OS (7.6.1 or 8.6) the CPU usage goes through the roof.

Idle
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Menu open
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I first used the 2010-11-06 build (64-bit and then in 32-bit mode) and then an older build (2009-10-25) but there was no change. Usage returns to normal once the menu is closed. This can be any menu: file, apple menu, control panels, context menu etc.

I've tried booting the emulated systems with extensions off in case a rogue one was to blame but the behaviour remains. Is this a known problem and is there any way to fix/minimise this?
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Ronald P. Regensburg
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Post by Ronald P. Regensburg »

I never noticed it, I never checked what happens when I pull down a menu in SheepShaver. When I check this now, I can see that it happens here also on my Intel Core 2 Duo iMac. I suppose it has always been there and no one noticed or cared.

It happens with other actions in SheepShaver. During startup of the virtual machine it is even worse, around 120% on my machine.

I am not sure if this should be called a "problem". Emulation is a CPU intensive task and SheepShaver has been a CPU hog always. I remember that, with some older builds on older machines, CPU use of SheepShaver never came below 90%, even in rest.

Maybe someone with the required programmer skills will take an interest and cares to try if CPU usage can be further reduced. There is nothing a user can do to change this.
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Amiganaut
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Joined: Fri Jul 24, 2009 2:44 pm

Post by Amiganaut »

I've since noticed that it does the same in Windows, which is where I've mostly used it over the last few years. I just never noticed the high CPU usage. Partly because I don't have any CPU monitoring software or widgets running (in OS X I have iStat menus) and partly because it only uses one core there (while it uses both in OS X).

So I guess it is normal behaviour. I did notice that switching between the 2010 and 2009 builds that while the older build would idle at @ 11%, the 2010 one would be in the mid 30s. So I'm using the 2009 one for the time being.
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Ronald P. Regensburg
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Post by Ronald P. Regensburg »

The 25 October 2009 build is probably still the better choice for most purposes on PPC Macs or as 32-bit application on Intel Macs.
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