From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from az33egw01.freescale.net (az33egw01.freescale.net [192.88.158.102]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "az33egw01.freescale.net", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTP id 70651DDE9E for ; Sat, 19 Jan 2008 09:48:36 +1100 (EST) Message-ID: <47912CDA.9020603@freescale.com> Date: Fri, 18 Jan 2008 16:48:58 -0600 From: Scott Wood MIME-Version: 1.0 To: DI BACCO ANTONIO - technolabs Subject: Re: ping 127.0.0.1 takes too much References: In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Cc: linuxppc-embedded@ozlabs.org List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , DI BACCO ANTONIO - technolabs wrote: > I have two different boards: one with MPC875 running at 66 MHz cpu/66 > MHz bus, one with MPC880 running at 132 MHz cpu /66MHz bus, I load the > same kernel and root file system on both the boards that have only > different u-boot(s). > > If I do a ping 127.0.0.1 on the MPC875 I get a round trip of 0.300 ms, > while on the other one I get 0.900 ms, I expected the opposite. > > Could be an issue with memory configuration? In the formula to calculate > the PTx on the MPC885RM manual I used 66 MHz as "system clock" for the > first board and 132 MHz for the second board. Probably this is a mistake > because "system clock" should be the bus clock but how this can so > adversely affect the ping round trip? Are you sure the timebase clock is what the kernel thinks it is? Does the time-of-day clock progress at the correct rate? -Scott