Comments on: Linux Disable Hyper Threading for Pentium 4 server GRUB boot loader

By: Wojciech

Wojciech — Sun, 10 Apr 2011 14:35:04 +0000

Well in my case HT does quite a lot of harm. An automatic test suite for an application I’m working detects number of processes and splits work load among them. Each test process spins its own application instance which is resource consuming. Even if HT gives some performance increase overall test time suffers.

I could hack test suite to detect HT and reduce number of processes by a factor of two. I’ll try to disable HT first.

By: Bill Broadley

Bill Broadley — Sat, 20 Dec 2008 02:04:44 +0000

Depends on the workload, for some server workloads it helps, for others it doesn’t. The new core i7 seems to have done this pretty well and I’m seeing a wider range of workloads where it helps.

By: bull

bull — Sat, 27 Jan 2007 04:03:12 +0000

For any type of server environment HT is beyond worthless. It will degrade your server application performance. HT is meant for interactive DESKTOP applications not DEADLINE based scheduling required by servers.

By: nixcraft

nixcraft — Thu, 23 Nov 2006 18:50:26 +0000

uname -a clearly indicates that you are running SMP kernel. SMP kernel enables HT and dual core support. So you don’t have to do anything.

To be frank enabling HT will increase your performance. However some application may not work (especially old apps). Those are rare cases and you need to disable HT.

By: concept10

concept10 — Thu, 23 Nov 2006 18:34:24 +0000

What are the pros/cons of disabling HT on P4 CPUs? I currently run Ubuntu 6.10 (Edgy) and the stock config/kernel has Hyper-Threading disabled. How do I enable this? May I enable this in GRUB or do I have to compile another kernel? uname -a > Linux ubuntu 2.6.17-10-generic #2 SMP