From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shirley Ma Subject: Re: [RFC PATCH 1/1] vhost: TX used buffer guest signal accumulation Date: Thu, 28 Oct 2010 13:13:55 -0700 Message-ID: <1288296835.11251.24.camel@localhost.localdomain> References: <1288216693.17571.38.camel@localhost.localdomain> <1288240804.14342.1.camel@localhost.localdomain> <20101028052021.GD5599@redhat.com> <1288294355.11251.20.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: David Miller , netdev@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org To: "Michael S. Tsirkin" Return-path: In-Reply-To: <1288294355.11251.20.camel@localhost.localdomain> Sender: kvm-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Thu, 2010-10-28 at 12:32 -0700, Shirley Ma wrote: > Also I found a big TX regression for old guest and new guest. For old > guest, I am able to get almost 11Gb/s for 2K message size, but for the > new guest kernel, I can only get 3.5 Gb/s with the patch and same > host. > I will dig it why. The regression is from guest kernel, not from this patch. Tested 2.6.31 kernel, it's performance is less than 2Gb/s for 2K message size already. I will resubmit the patch for review. I will start to test from 2.6.30 kernel to figure it when TX regression induced in virtio_net. Any suggestion which guest kernel I should test to figure out this regression? Thanks Shirley