From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932114AbVHRDBD (ORCPT ); Wed, 17 Aug 2005 23:01:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932117AbVHRDBC (ORCPT ); Wed, 17 Aug 2005 23:01:02 -0400 Received: from smtp203.mail.sc5.yahoo.com ([216.136.129.93]:50099 "HELO smtp203.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S932114AbVHRDBA (ORCPT ); Wed, 17 Aug 2005 23:01:00 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=e6mhjy+Mnp35eXa3Go2tifvmKN76TRnLcyF9M25VvzJCM0IUbnDSdZBudV2RH0MurKviJv7v6h3uiSO0F7rwaEy+wPjQv3FRA9dD+nBNftMoJy8Grr+vIMcNsRhJ1QZl5AX6SlR+YxezFQuPy2mNQipW978vD2bFpsI9Hje6C2g= ; Message-ID: <4303F9E6.8030607@yahoo.com.au> Date: Thu, 18 Aug 2005 13:00:54 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.8) Gecko/20050513 Debian/1.7.8-1 X-Accept-Language: en MIME-Version: 1.0 To: Andi Kleen CC: Eric Dumazet , Benjamin LaHaise , "David S. Miller" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] struct file cleanup : the very large file_ra_state is now allocated only on demand. References: <20050810164655.GB4162@linux.intel.com> <20050810.135306.79296985.davem@davemloft.net> <20050810211737.GA21581@linux.intel.com> <430391F1.9080900@cosmosbay.com> <20050817211829.GK27628@wotan.suse.de> <4303AEC4.3060901@cosmosbay.com> <20050817215357.GU3996@wotan.suse.de> <4303D90E.2030103@cosmosbay.com> <20050818010524.GW3996@wotan.suse.de> <4303F7E8.5030705@yahoo.com.au> <20050818025727.GY3996@wotan.suse.de> In-Reply-To: <20050818025727.GY3996@wotan.suse.de> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andi Kleen wrote: >>You don't want to always have bad performance though, so you >>could attempt to allocate if either the pointer is null _or_ it >>points to the global structure? >> > >Remember it's after a GFP_KERNEL OOM. If that fails most likely >you have deadlocked somewhere else already because Linux's handling >of that is so bad. Suboptimal readahead somewhere is the smallest >of your problems. > > True. And in practice it may not even be able to happen at the moment if the page allocator still doesn't fail small order allocs. But I guess the dream one day is to robustly handle any OOM :\ Send instant messages to your online friends http://au.messenger.yahoo.com