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When programs on my laptop crash, they sometimes start hogging CPU. I have noticed that some processes use 50% (like firefox, various games) but a few use 100% like (VLC, GOM) etc.

Does this have do with Core2Duo processor on my laptop? Also what determines whether they will use 50% or 100%?

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Single-threaded applications will use 50%, or one of the cores on the system fully. Multi-threaded apps will use 100%, or both cores.

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I find it hard to believe that firefox would be running on a single thread. – apoorv020 May 11 '11 at 10:33
You're welcome to pick through the source code. – Ignacio Vazquez-Abrams May 11 '11 at 10:38
@apoorv020 It may only take a single thread/process to hog a CPU core for the entire application to hang. – sblair May 11 '11 at 10:42
It would be more accurate to say that if the portion of the program that was using the processing power is single-threaded, it will not use more than 50% CPU on a Dual Core (or 25% on a Quad Core). – sgmoore May 11 '11 at 10:43

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