Thread: Why does a conversion thread never use more than 25% of CPU?
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Old 01-26-2016, 09:41 AM   #1
HarryT
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Why does a conversion thread never use more than 25% of CPU?
My rather elderly laptop has a dual-core i5 processor (state of the art when I bought it many years ago ), and I notice that, when I convert books, even if there's only one "calibre-parallel" conversion thread running, Windows Task Manager shows that the conversion thread never exceeds 25% CPU usage.

At first I thought that this meant that it was running one CPU core flat out but, given that I have a dual- rather than a quad-core CPU, this is not the case; it's never running a CPU core at more than 50% capacity.

Is this a limit imposed by Calibre itself (or its library) or is it something to do with my PC? I ask merely out of curiosity.

Thanks,
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