Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 17 Oct 2001 06:57:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 17 Oct 2001 06:57:40 -0400 Received: from inway106.cdi.cz ([213.151.81.106]:30598 "EHLO luxik.cdi.cz") by vger.kernel.org with ESMTP id ; Wed, 17 Oct 2001 06:57:34 -0400 Posted-Date: Wed, 17 Oct 2001 12:58:06 +0200 Date: Wed, 17 Oct 2001 12:58:05 +0200 (CEST) From: Martin Devera To: lkml Subject: NET_PROFILE results for 2.4.12 [was sentto is slow] In-Reply-To: <3BCD56A2.B5362224@loewe-komp.de> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, In my previous posts I was thinking why my PII/375 system can't handle more than 25000 packet/s. I repaired kernel's NET_PROFILEr and got an answer. So that for curious, first gprof output of program doing send/poll/recv of 200 byte packets loop on the loopback interface using PF_PACKET (total running time was 20 sec): 49.67 9.93 9.93 549384 0.02 0.02 sendto 17.71 13.47 3.54 549384 0.01 0.01 recv 12.01 15.87 2.40 553784 0.00 0.00 poll Now we compare them with kernel profile stats: af_packet_send: 7876 ms nested dev_queue_xmit: 3714 ms net_rx_action: 1464 ms af_packet_recv: 411 ms For send gprof tells 9930 ms and kernel 7876 so 2 sec in difference is generic socket and system call handling overhead (and measure error). The recv gproffed is 3540 ms, kernel 1464+411 so there is again about 2 sec overhead. >From this analysis I can finally say that there is not error in my netflow simulator :) but the 2.4 on PII/375 can handle up to 30000 pps in userspace loop. Without userspace overhead and not bouncing packets (like in my test) the router based on 2.4 could handle about 70000 pps without qos,routing and filtering overhead .. Someone tested in real world ? best regards, devik - 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/