From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Christie Subject: Re: [PATCH] target/user: Add daynmic growing data area feature support Date: Mon, 27 Feb 2017 17:56:21 -0600 Message-ID: <58B4BCA5.2060002@redhat.com> References: <1487323472-20481-1-git-send-email-lixiubo@cmss.chinamobile.com> <09891673-0d95-8b66-ddce-0ace7aea43d1@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: Received: from mx1.redhat.com ([209.132.183.28]:50330 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751478AbdB0X7m (ORCPT ); Mon, 27 Feb 2017 18:59:42 -0500 In-Reply-To: <09891673-0d95-8b66-ddce-0ace7aea43d1@redhat.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Andy Grover , lixiubo@cmss.chinamobile.com, nab@linux-iscsi.org, shli@kernel.org Cc: hch@lst.de, sheng@yasker.org, namei.unix@gmail.com, bart.vanassche@sandisk.com, linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, linux-kernel@vger.kernel.org, Jianfei Hu , Venky Shankar On 02/22/2017 02:32 PM, Andy Grover wrote: > On 02/17/2017 01:24 AM, lixiubo@cmss.chinamobile.com wrote: >> > From: Xiubo Li >> > >> > Currently for the TCMU, the ring buffer size is fixed to 64K cmd >> > area + 1M data area, and this will be bottlenecks for high iops. > Hi Xiubo, thanks for your work. > > daynmic -> dynamic > > Have you benchmarked this patch and determined what kind of iops > improvement it allows? Do you see the data area reaching its > fully-allocated size? > I tested this patch with Venky's tcmu-runner rbd aio patches, with one 10 gig iscsi session, and for pretty basic fio direct io (64 -256K read/writes with a queue depth of 64 numjobs between 1 and 4) tests read throughput goes from about 80 to 500 MB/s. Write throughput is pretty low at around 150 MB/s. I did not hit the fully allocated size. I did not drive a lot of IO though.