[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Debian hyperthreading support

On 10/2/2010 6:08 PM, Nathen wrote:
Pretty simple question really, does Debian i.e. the current Linux
Kernel handle hyperthreading well? I have a server running on an Intel
Atom D510, should I have HT enabled or disabled to get the best
Thanks. :)

Recently (kernel 2.6.31 or so) there has been a separate kernel configuration option to optimize for SMT (Intel's word for it is "hyperthreading"). Separate from SMP (multiple processor). Under SMT, a single core running two threads looks like two cores to most of the kernel itself and to user programs. This has been true for a long time. Only now, there is more support and optimization for it. If your kernel has it enabled, some workloads won't see any difference, but some will benefit a lot. I think it is enabled by default in the most recent stock kernels (please correct me if I'm wrong.)

Note, you may need to enable hyperthreading in your BIOS, as well.

I would enable it for Core i7 and Atom. P4-era machines could sometimes have software compatibility issues with it enabled, but I think Debian and Atoms are good.

Reply to: