From owner-freebsd-hackers Fri Jan 25 9: 1:42 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from patrocles.silby.com (d57.as12.nwbl0.wi.voyager.net [169.207.135.57]) by hub.freebsd.org (Postfix) with ESMTP id 4AE5637B404 for ; Fri, 25 Jan 2002 09:01:36 -0800 (PST) Received: from localhost (silby@localhost) by patrocles.silby.com (8.11.6/8.11.6) with ESMTP id g0PB4X608595; Fri, 25 Jan 2002 11:04:54 GMT (envelope-from silby@silby.com) X-Authentication-Warning: patrocles.silby.com: silby owned process doing -bs Date: Fri, 25 Jan 2002 11:04:32 +0000 (GMT) From: Mike Silbersack To: Dmitry Mottl Cc: freebsd-hackers@freebsd.org Subject: Re: strange TCP slowness... In-Reply-To: Message-ID: <20020125110114.B8543-100000@patrocles.silby.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Fri, 25 Jan 2002, Dmitry Mottl wrote: > Hi, All > > Sorry, for posting a big dump, but it is needed for understanding > the problem. > > I have very slow tcp connection between two computers on the same LAN > This computers uses FreeBSD 4.4 GENERIC kernel > > This is a TCPDUMP for and passive ftp transfer > > As you can see the transfer stops every 1 second!!! > So the question is WHY?? > All sysctl variables are identical > I'm not using firewalls or traffic shappers Well, from this trace it's clear that packet loss is occuring; the 1 second delays are retransmit timeouts, nothing unexpected there. As far as I can tell from looking at the trace, the problem is not a fault in FreeBSD's tcp stack, but rather something hardware related. I'd suggest changing network cards on host A to see if that makes a difference. Mike "Silby" Silbersack To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message