# SCHED_SMT for corei ?

## Massimo B.

Hi, this CPU is a i7-2620M.

Which of these kernel options is recommended? CONFIG_SCHED_MC or CONFIG_SCHED_SMT or both? Physically this CPU has 2 cores but each with hyperthreading, resulting in 4 logical cores. So this is both a multicore but also hyperthreaded CPU which is common today, though I would prefer 4 real cores.

The docs of SCHED_SMT only describe the P4 or Core2, not the core-i:  *Quote:*   

> SMT scheduler support improves the CPU scheduler's decision making when dealing with Intel P4/Core 2 chips with HyperThreading at a  cost of slightly increased overhead in some places.

 

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## eccerr0r

Both

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## Massimo B.

Thanks.

btw, what do you think about WQ_POWER_EFFICIENT_DEFAULT on the Mobile core-i in a Laptop, is that worth the power saving or is the loss of cpu performance too much? I also think about less heating and cooling, but performance has highest priority.

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## eccerr0r

Up to you.

Depends on your application on how much penalty scheduling threads on different queues will be.

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