From mboxrd@z Thu Jan 1 00:00:00 1970 From: Diwaker Gupta Subject: Re: Xen cluster n/w performance (again!) Date: Tue, 23 Nov 2004 13:32:59 -0800 Message-ID: <1b0b4557041123133226ff88@mail.gmail.com> References: Reply-To: Diwaker Gupta Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: xen-devel-admin@lists.sourceforge.net Errors-To: xen-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Keir Fraser Cc: xen-devel@lists.sourceforge.net List-Id: xen-devel@lists.xenproject.org > One thing you might want to try is to change a line in the file > linux-2.6.9-xenU/drivers/xen/netfront/netfront.c. > From: > #define RX_MIN_TARGET 8 > To: > #define RX_MIN_TARGET NETIF_RX_RING_SIZE > > One possibility is that dynamic buffer sizing is dropping some packets > and causing TCP to crap itself. > > If this improves things then I'll have to be much more careful about > shrinking the buffers, and/or add a config option to disable the > resizing completely. > > -- Keir > My bad. Sorry about the false alarm everyone, it was a routing issue. With the correct routing setup, I can see upto 930 Mbps between VMs running on 2 distinct physical machines in the cluster. Cheers! -- Diwaker Gupta http://resolute.ucsd.edu/diwaker ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/