Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935289AbZLMB5z (ORCPT ); Sat, 12 Dec 2009 20:57:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S935256AbZLMB5x (ORCPT ); Sat, 12 Dec 2009 20:57:53 -0500 Received: from mail-pw0-f42.google.com ([209.85.160.42]:43463 "HELO mail-pw0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S933426AbZLMB5w (ORCPT ); Sat, 12 Dec 2009 20:57:52 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; b=ipW+QZzpnfR+4zrzJtQUep82mEAhhHHgJmAJ3ja+nE0uhVLgU83J6dFJymxUx4yj1T nKiSU3FCChiWwU1IUdkWBM0TZnU/cW8l3JyJNr/u01dG7T1S+c9swu497CqJ8SHUqaDT OYSjv8U9Pwd3/5qY8ySvZObP3yHvFEaCGu01Q= MIME-Version: 1.0 In-Reply-To: <86802c440912121705y59eea3ebq3bdbd3e7459e748e@mail.gmail.com> References: <86802c440912112125v4aa72189ifcc2d16ecbf79cc4@mail.gmail.com> <20091211.214117.200029438.davem@davemloft.net> <86802c440912121705y59eea3ebq3bdbd3e7459e748e@mail.gmail.com> Date: Sat, 12 Dec 2009 17:57:51 -0800 X-Google-Sender-Auth: 140f87d424c73efd Message-ID: <86802c440912121757g474a7df4od6b50f6d5a210cf0@mail.gmail.com> Subject: Re: nfs broken in net-next? -- now in mainline -- bisected: d9f5950f90292f7cc42834338dfd5f44dc4cc4ca From: Yinghai Lu To: David Miller , Eric Dumazet Cc: mingo@elte.hu, sri@us.ibm.com, herbert@gondor.apana.org.au, torvalds@linux-foundation.org, sjayaraman@suse.de, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1791 Lines: 49 On Sat, Dec 12, 2009 at 5:05 PM, Yinghai Lu wrote: > > [f86dcc5aa8c7908f2c287e7a211228df599e3e71] udp: dynamically > size hash tables at boot time commit f86dcc5aa8c7908f2c287e7a211228df599e3e71 Author: Eric Dumazet Date: Wed Oct 7 00:37:59 2009 +0000 udp: dynamically size hash tables at boot time UDP_HTABLE_SIZE was initialy defined to 128, which is a bit small for several setups. 4000 active UDP sockets -> 32 sockets per chain in average. An incoming frame has to lookup all sockets to find best match, so long chains hurt latency. Instead of a fixed size hash table that cant be perfect for every needs, let UDP stack choose its table size at boot time like tcp/ip route, using alloc_large_system_hash() helper Add an optional boot parameter, uhash_entries=x so that an admin can force a size between 256 and 65536 if needed, like thash_entries and rhash_entries. dmesg logs two new lines : [ 0.647039] UDP hash table entries: 512 (order: 0, 4096 bytes) [ 0.647099] UDP Lite hash table entries: 512 (order: 0, 4096 bytes) Maximal size on 64bit arches would be 65536 slots, ie 1 MBytes for non debugging spinlocks. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller cause the problem: nfs mount fail. the setup is: 64bit kernel, have all needed drivers in kernel, and boot with ip=dhcp, root disk is 256M ramdisk. then try to mount nfs.... YH -- 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/