From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261445AbVFTSvT (ORCPT ); Mon, 20 Jun 2005 14:51:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261446AbVFTSvT (ORCPT ); Mon, 20 Jun 2005 14:51:19 -0400 Received: from tetsuo.zabbo.net ([207.173.201.20]:708 "EHLO tetsuo.zabbo.net") by vger.kernel.org with ESMTP id S261445AbVFTSvQ (ORCPT ); Mon, 20 Jun 2005 14:51:16 -0400 Message-ID: <42B71025.6040006@zabbo.net> Date: Mon, 20 Jun 2005 11:51:17 -0700 From: Zach Brown User-Agent: Mozilla Thunderbird 1.0.2-1.3.3 (X11/20050513) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Benjamin LaHaise Cc: Suparna Bhattacharya , linux-aio@kvack.org, linux-kernel@vger.kernel.org, wli@holomorphy.com, mason@suse.com, ysaito@hpl.hp.com Subject: Re: Pending AIO work/patches References: <20050620120154.GA4810@in.ibm.com> <20050620181007.GA4031@kvack.org> In-Reply-To: <20050620181007.GA4031@kvack.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org >>(6) epoll - AIO integration (Zach Brown/Feng Zhou/wli) >> Status: Needs resurrection ? > > > What are folks thoughts in this area? Zach's patches took the approach of > making multishot iocbs possible, which helped avoid the overhead of plain > aio_poll's command setup, which was quite visible in pipetest. Zach -- did > you do any benchmarking on your aio-epoll patches? No, what little work I did on this was just pushing for stable functionality. I had a little test app that was still missing event delivery occasionally. I'm sure it'd be easy enough to track down. It still seems like a pretty reasonable translation of epoll event delivery through the aio completion queue. I'm not thrilled with the epoll edge delivery semantics, though, it would be nice to make duplicate event generation contigent on servicing an initial event. EPOLLIN being throttled until read activity is seen on the fd, that kind of thing. Nontrivial work, of course. >>(7) Vector AIO (aio readv/writev) (Yasushi Saito) >> Status: Needs resurrection ? > > Zach also made some noises about this recently... Yeah, I've got a patch working that adds CMD_AIO_P{WRITE,READ}V for ext3 via some aio->aio_p{read,werive}v ops. It's currently against some distro 2.6, but I'll port it up to current and post the patch. It seems pretty noncontroversial -- one obviously wants to scatter/gather file-contiguous IO with tiny iovec elements, which bubble down well to the generic fs/block helpers, rather than trying to get the various layers to merge many large iocb submissions that can be found to be file-contiguous. - z