[Asterisk-Users] Hyperthreading?

Peter Corlett abuse at cabal.org.uk
Tue Jun 1 07:08:34 MST 2004

Andrew Kohlsmith <akohlsmith-asterisk at benshaw.com> wrote:
> They can't? HT is detected in /proc/cpuinfo (flags) and I see two
> processors with 2.4.25 SMP kernels... What exactly isn't it using?

Linux doesn't realise that scheduling a process onto one virtual CPU
reduces the performance available on the other. There can be some
quite bizarre scheduling decisions made as a result that can slow
things down. On the other hand, for some tasks, it might not cause
problems and thus you'll get a boost.

As ever, the answer is to benchmark your configuration with and
without HT to see. There's no simple answer.

PGP key ID E85DC776 - finger abuse at mooli.org.uk for full key

More information about the asterisk-users mailing list