From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: Weekly performance meeting Date: Fri, 26 Sep 2014 06:02:39 -0700 Message-ID: <20140926130239.GA4577@infradead.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from bombadil.infradead.org ([198.137.202.9]:40724 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754590AbaIZNCp (ORCPT ); Fri, 26 Sep 2014 09:02:45 -0400 Content-Disposition: inline In-Reply-To: Sender: ceph-devel-owner@vger.kernel.org List-ID: To: Milosz Tanski Cc: Dong Yuan , Haomai Wang , Sage Weil , "ceph-devel@vger.kernel.org" , Somnath Roy , Allen Samuels , Kasper Dieter , PVonStamwitz@us.fujitsu.com, "Shu, Xinxin" , Stefan Priebe - Profihost AG , xiaoxi.chen@intel.com, "Wang, Zhiqiang" , jianpeng.ma@intel.com, gdror@mellanox.com, vuhuong@mellanox.com, Mark Nelson On Fri, Sep 26, 2014 at 08:58:56AM -0400, Milosz Tanski wrote: > First, I have recently submitted a series of patches to kernel to add > a new preadv2 syscall that lets you do a "fast read" out of the page > cache the point being that you can skip the whole disk IO queue in > user space in the cases it's already cached (thus reducing the > latency). Obviously this doesn't do much for writes (yet, Christoph > Heldwig is working on that). Samba expressed an interest using these > new syscalls as well. We could also implement it for writes, but if would be a bit more complicated. If there is a compelling use case it might be worth exploring.