Re: Hardware limits on numbers of threads?

From: Brian Gerst (
Date: Wed Sep 18 2002 - 06:57:11 EST

Dan Kegel wrote:
> says:
>>Hardware restrictions put hard limits on the number of
>>threads the kernel can support for each process.
>>Specifically this applies to IA-32 (and AMD x86_64) where the thread
>>register is a segment register. The processor architecture
>>puts an upper limit on the number of segment register values
>>which can be used (8192 in this case).
> Is this true? Where does the limit come from?
> - Dan

A long time ago Linux did use one GDT segment for a TSS and LDT for each
process. Then it was changed in 2.3.11 to have one TSS and LDT per cpu,
removing the limit on the number of processes that can exist in the system.

				Brian Gerst

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