From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964976AbWD0Lo2 (ORCPT ); Thu, 27 Apr 2006 07:44:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964986AbWD0Lo2 (ORCPT ); Thu, 27 Apr 2006 07:44:28 -0400 Received: from ns.virtualhost.dk ([195.184.98.160]:11868 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id S964976AbWD0Lo2 (ORCPT ); Thu, 27 Apr 2006 07:44:28 -0400 Date: Thu, 27 Apr 2006 13:45:06 +0200 From: Jens Axboe To: KAMEZAWA Hiroyuki Cc: akpm@osdl.org, linux-kernel@vger.kernel.org, npiggin@suse.de, linux-mm@kvack.org Subject: Re: Lockless page cache test results Message-ID: <20060427114506.GE23137@suse.de> References: <20060426135310.GB5083@suse.de> <20060426095511.0cc7a3f9.akpm@osdl.org> <20060426174235.GC5002@suse.de> <20060426185750.GM5002@suse.de> <20060427111937.deeed668.kamezawa.hiroyu@jp.fujitsu.com> <20060427080316.GL9211@suse.de> <20060427111625.GD23137@suse.de> <20060427204132.2150e5cb.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060427204132.2150e5cb.kamezawa.hiroyu@jp.fujitsu.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 27 2006, KAMEZAWA Hiroyuki wrote: > On Thu, 27 Apr 2006 13:16:25 +0200 > Jens Axboe wrote: > > > Added, 1 vs 2/3/4 clients isn't very interesting, so to keep it short > > here are numbers for 2 clients to /dev/null and localhost. > > > Thank you! looks splice has significant advantage :) > > > Sending to /dev/null > > > > ml370:/data # ./splice-bench -n2 -l10 -a -s -z file > > Waiting for clients > > Client1 (splice): 19030 MiB/sec (10240MiB in 551 msecs) > > Client0 (splice): 18961 MiB/sec (10240MiB in 553 msecs) > This maybe shows cost of gathering page-cache. Precisely, it's basically the cost of looking up the pages and adding them to the pipe. > > Client1 (mmap): 158875 MiB/sec (10240MiB in 66 msecs) > > Client0 (mmap): 158875 MiB/sec (10240MiB in 66 msecs) > This shows read/write system-call and user program cost. right ? It shows the cost of write()'ing the mmap'ed file area to /dev/null. > > Client1 (rw): 1691 MiB/sec (10240MiB in 6200 msecs) > > Client0 (rw): 1690 MiB/sec (10240MiB in 6201 msecs) > > > This shows 10240MiB copy_to_user() cost. > BTW, How big are cpu-cache-size and read/write buffer size in this test ? This was done on a xeon with 2mb l2. The buffers size used was 64k in all cases. > > Sending/receiving over lo > > > read from a file and write to lo ? I'd rather say input is a file and output is a socket going to lo, that is a little more precisely given the differing methods the clients use. But I suspect this is what you meant. -- Jens Axboe