Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 9 Jan 2003 16:49:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 9 Jan 2003 16:49:37 -0500 Received: from main.gmane.org ([80.91.224.249]:55239 "EHLO main.gmane.org") by vger.kernel.org with ESMTP id ; Thu, 9 Jan 2003 16:49:35 -0500 X-Injected-Via-Gmane: http://gmane.org/ To: linux-kernel@vger.kernel.org Path: not-for-mail From: Jason Lunz Subject: Re: detecting hyperthreading in linux 2.4.19 Date: Thu, 9 Jan 2003 21:57:09 +0000 (UTC) Organization: PBR Streetgang Message-ID: References: <200301091337.04957.jamesclv@us.ibm.com> X-Complaints-To: usenet@main.gmane.org User-Agent: slrn/0.9.7.4 (Linux) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1119 Lines: 18 jamesclv@us.ibm.com said: > I don't know of any way to do this in userland. The whole point is > that the sibling processors are supposed to look like real ones. That's unfortunately not always true. I'm writing a program that will run on a system that will be doing high-load routing. Testing has shown that we get better performance when binding each NIC's interrupts to a separate physical processor using /proc/irq/*/smp_affinity (especially when all the interrupts would hit the first CPU, another problem i've yet to address). That only works for real processors, though, not HT siblings. I'm writing a program to run on machines of unknown (by me) configuration, that will spread out the NIC interrupts appropriately. So userspace needs to know the difference, at least until interrupts can be automatically distributed by the kernel in a satisfactory way. Jason - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/