From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nick Piggin Subject: Re: [PATCH] struct file cleanup : the very large file_ra_state is now allocated only on demand. Date: Thu, 18 Aug 2005 13:00:54 +1000 Message-ID: <4303F9E6.8030607@yahoo.com.au> 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> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Cc: Eric Dumazet , Benjamin LaHaise , "David S. Miller" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Return-path: To: Andi Kleen In-Reply-To: <20050818025727.GY3996@wotan.suse.de> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.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