Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753639Ab3F0JIk (ORCPT ); Thu, 27 Jun 2013 05:08:40 -0400 Received: from mail-pb0-f47.google.com ([209.85.160.47]:52162 "EHLO mail-pb0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752502Ab3F0JIe (ORCPT ); Thu, 27 Jun 2013 05:08:34 -0400 Message-ID: <51CC010D.70503@numascale-asia.com> Date: Thu, 27 Jun 2013 17:08:29 +0800 From: Daniel J Blueman Organization: Numascale Asia User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130510 Thunderbird/17.0.6 MIME-Version: 1.0 To: Eric Dumazet CC: Linux Kernel , Ingo Molnar , Steffen Persvold Subject: Re: 13GB dcache+inode cache hash tables References: <51C95B3A.10809@numascale-asia.com> <1372153697.3301.98.camel@edumazet-glaptop> In-Reply-To: <1372153697.3301.98.camel@edumazet-glaptop> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1296 Lines: 35 On 25/06/2013 17:48, Eric Dumazet wrote: > On Tue, 2013-06-25 at 16:56 +0800, Daniel J Blueman wrote: >> As memory capacity increases, we see the dentry and inode cache hash >> tables grow to wild sizes [1], eg 13GB is consumed on a 4.5TB system. >> >> Perhaps a better approach adds a linear component to an exponent to give >> tuned scaling, given that spatial locality is an advantage in hash table >> and careful use of resources. >> >> The same approach would fit to other hash tables (mount-cache, TCP >> established, TCP bind, UDP, UDP-Lite, Dquot-cache) with different >> coefficients, so perhaps we could generalise. >> > > TCP hash table is limited to 512K slots, unless overridden. > TCP bind limited to 64K slots. > UDP limited to 64K slots. > >> If so what are reasonable reference points and assumptions? > > I do not know what you have in mind, please show us a patch ;) [...] Alright, I'll see what I can get together in the next week or so when I can fit it in. Dan -- Daniel J Blueman Principal Software Engineer, Numascale Asia -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/