Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 7 Feb 2003 13:39:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 7 Feb 2003 13:39:23 -0500 Received: from mta02-svc.ntlworld.com ([62.253.162.42]:4565 "EHLO mta02-svc.ntlworld.com") by vger.kernel.org with ESMTP id convert rfc822-to-8bit; Fri, 7 Feb 2003 13:39:22 -0500 Content-Type: text/plain; charset="us-ascii" From: SA To: linux-kernel@vger.kernel.org Subject: interrupt latency k2.4 / i386? Date: Fri, 7 Feb 2003 18:47:36 +0000 User-Agent: KMail/1.4.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT Message-Id: <200302071847.36646.bullet.train@ntlworld.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1147 Lines: 33 Dear list, What latency should I expect for hardware interrupts under k2.4 / i386 ? ie how long should it take between the hardware signalling the interrupt and the interrupt handler being called? I am wrting a driver which pace IO with interrupts, generating one interrupt for after every transfer is done. Looking at the hardware schematics the interrupts should occur virtually instantly after each transfer but the driver is waiting ~1ms/ interrupt. I can use polling instead with busy waits but this seems a bit wasteful. My interrupt is shared with my graphics card using the non-GPL nvidia driver - could this be responsible for the delay (any experience with this)? cat /proc/interrupts ..... 10: 3028 XT-PIC eth0, VIA 82C686A 11: 1117037 XT-PIC nvidia, PI stage <-- my driver 12: 14776 XT-PIC usb-uhci, usb-uhci ..... Thanks SA - 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/