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From: "Andrew Edwards (Olympic Shaver Centre)" <andrew@shavers.co.uk>
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Date: Wed, 14 Jan 2004 11:15:42 -0000
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Subject: Hyperthreading with SMP in 5.2
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Hi,

Could anyone clarify the level of support for Pentium 4 hyperthreading =
in 5.2? I understand that the kernel is now smp aware by default but =
does it handle the logical cpu's of hyperthreading in the same manner as =
it would a physical cpu?

I ask as for the best part my machine rarely goes above 50% cpu =
utilisation. However using -j2 when building the kernel or world for =
example will give me nearer full use, which I can appreciate as it =
generates concurrent processes that likely get divided over the two =
logical cpu.

Not being fully aware of the technical bits to hyperthreading is the =
above scenario as good as it can be and is making good use of the cpu, =
i.e if I run a single cpu heavy process, whereas without hyperthreading =
I would see 100% usage now I only see around 50%.

Thanks.