topic Re: Hyper-threading in Operating System - Linux

Hyper-threading

Grio — Sun, 13 Jan 2008 16:28:46 GMT

OS: SLES 9 running on a DL585
the OS is correctly showing it has 8 cpus.
but
hpasmcli -s "show ht"
Processor hyper-threading is currently disabled.

the question is will i gain anything by enabling HT?

thanks

Re: Hyper-threading

Stuart Browne — Mon, 14 Jan 2008 01:00:40 GMT

You're using AMD Opteron processors, in a 585 chassis. The chassis can only have 4 physical processors, so the dual-core enabled processors are already showing as fully enabled.

'Hyper-threading' is an Intel mechanism introduced in the P4 era (later included in the Xeon series) as a prelude to 'multi-core' processors. Now it's just a dual-core/quad-core processor, instead of 'Hyper-trheading'.

Yes, there are differences between multi-core and hyper-threading, but the Linux OS treats them (at the user level at least) as separate processors.

Re: Hyper-threading

Grio — Mon, 14 Jan 2008 15:55:08 GMT

thanks