From owner-freebsd-current@FreeBSD.ORG Mon Jan 31 10:21:52 2005 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 905F816A4CE for ; Mon, 31 Jan 2005 10:21:52 +0000 (GMT) Received: from critter.freebsd.dk (f170.freebsd.dk [212.242.86.170]) by mx1.FreeBSD.org (Postfix) with ESMTP id C666B43D39 for ; Mon, 31 Jan 2005 10:21:51 +0000 (GMT) (envelope-from phk@critter.freebsd.dk) Received: from critter.freebsd.dk (localhost [127.0.0.1]) by critter.freebsd.dk (8.13.1/8.13.1) with ESMTP id j0VALoCe088176 for ; Mon, 31 Jan 2005 11:21:50 +0100 (CET) (envelope-from phk@critter.freebsd.dk) To: current@freebsd.org From: Poul-Henning Kamp Date: Mon, 31 Jan 2005 11:21:50 +0100 Message-ID: <88175.1107166910@critter.freebsd.dk> Sender: phk@critter.freebsd.dk Subject: network performance, a low-level measurement X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 31 Jan 2005 10:21:52 -0000 In case anybody can use this for anything: Setup: o Soekris NET4501 (133Mhz AMD Elan CPU) o -Current o stripped down kernel. o no SMP, no WITNESS, no DIAGNOSTIC o unshared interrupt line o if_sis driver modified to FAST intr which just schedules the existing sis_intr on taskqueue_fast o single-user mode o A back-to-back cable to another machine. o A single default sized ping packet Time [uSec] Where ----------------------------------------------------------------------- 000.000 HW-intr start 011.600 HW-intr stop 067.200 Enter sis_intr_task() 074.000 Enter sis_rxeof() 134.800 Enter ifp->if_input() 552.800 Enter sis_startl() 595.600 Exit sis_startl() 753.200 Return from ifp->if_input() 758.000 Exit sis_rxeof() 761.200 Enter sis_txeof() 796.400 Exit sis_txeof() 800.200 Exit sis_intr_task() ----------------------------------------------------------------------- Driver Other [uSec] [uSec] ------------------------------------------------------- HW-intr duration: 11.600 Taskqueue_fast Latency: 55.600 sis_rxeof() duration: 65.500 ifp->if_input() duration: 575.700 sis_startl() duration: 42.800 sis_txeof() duration: 35.200 sis_intr_task duration: 13.800 ------------------------------------------------------- Total 168.900 631.300 ======================================================= Summary: 21% of the time spent in the driver. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.