Re: Why can OS kernel only use maximum 2GB memory?

Liang Yang wrote:
Hi,

For a 32 bit OS running on a 32bit IA processor, why is 2GB the maximum memory used by OS kernel while application process can use more than 2GB memory? Which factor decide this limitation?

Thanks,

Liang

Crap run time libraries using signed integers for memory management and stuff like that. Apart from this there is no such limitation. As far as NT based OS-s you can override the default 2GB limitation by using a startup command line switch (that I am too lazy to look up for you) which would provide a 3GB address space to applications. The remaining 1GB of address space is reserved for the OS. This is not an IA32 architectural thing but rather merely an OS design decision.

.

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