From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: [RFC PATCH 04/20] Make QEMUFile buf expandable, and introduce qemu_realloc_buffer() and qemu_clear_buffer(). Date: Fri, 23 Apr 2010 08:26:03 -0500 Message-ID: <4BD19FEB.1040804@linux.vnet.ibm.com> References: <1271829445-5328-1-git-send-email-tamura.yoshiaki@lab.ntt.co.jp> <1271829445-5328-5-git-send-email-tamura.yoshiaki@lab.ntt.co.jp> <4BD16E30.5080502@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Yoshiaki Tamura , kvm@vger.kernel.org, qemu-devel@nongnu.org, Anthony Liguori , mtosatti@redhat.com, ohmura.kei@lab.ntt.co.jp, yoshikawa.takuya@oss.ntt.co.jp To: Avi Kivity Return-path: Received: from e2.ny.us.ibm.com ([32.97.182.142]:58560 "EHLO e2.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754064Ab0DWN0M (ORCPT ); Fri, 23 Apr 2010 09:26:12 -0400 Received: from d01relay06.pok.ibm.com (d01relay06.pok.ibm.com [9.56.227.116]) by e2.ny.us.ibm.com (8.14.3/8.13.1) with ESMTP id o3NDEh30021514 for ; Fri, 23 Apr 2010 09:14:43 -0400 Received: from d01av03.pok.ibm.com (d01av03.pok.ibm.com [9.56.224.217]) by d01relay06.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o3NDQ7r4839688 for ; Fri, 23 Apr 2010 09:26:07 -0400 Received: from d01av03.pok.ibm.com (loopback [127.0.0.1]) by d01av03.pok.ibm.com (8.14.3/8.13.1/NCO v10.0 AVout) with ESMTP id o3NDQ5SE005119 for ; Fri, 23 Apr 2010 10:26:07 -0300 In-Reply-To: <4BD16E30.5080502@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 04/23/2010 04:53 AM, Avi Kivity wrote: > On 04/21/2010 08:57 AM, Yoshiaki Tamura wrote: >> Currently buf size is fixed at 32KB. It would be useful if it could >> be flexible. >> > > Why is this needed? The real buffering is in the kernel anyways; this > is only used to reduce the number of write() syscalls. With vmstate, we really shouldn't need to do this magic anymore as an optimization. Regards, Anthony Liguori