From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f199.google.com (mail-pf1-f199.google.com [209.85.210.199]) by kanga.kvack.org (Postfix) with ESMTP id CAEC28E0001 for ; Tue, 22 Jan 2019 16:44:17 -0500 (EST) Received: by mail-pf1-f199.google.com with SMTP id s71so22363pfi.22 for ; Tue, 22 Jan 2019 13:44:17 -0800 (PST) Received: from mga02.intel.com (mga02.intel.com. [134.134.136.20]) by mx.google.com with ESMTPS id f5si11526028pfn.259.2019.01.22.13.44.16 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 22 Jan 2019 13:44:16 -0800 (PST) From: Andi Kleen Subject: Re: [LSF/MM TOPIC] Page flags, can we free up space ? References: <20190122201744.GA3939@redhat.com> Date: Tue, 22 Jan 2019 13:44:15 -0800 In-Reply-To: <20190122201744.GA3939@redhat.com> (Jerome Glisse's message of "Tue, 22 Jan 2019 15:17:44 -0500") Message-ID: <87tvi074gg.fsf@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: Jerome Glisse Cc: lsf-pc@lists.linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Jerome Glisse writes: > > Right now this is more a temptative ie i do not know if i will succeed, > in any case i can report on failure or success and discuss my finding to > get people opinions on the matter. I would just stop putting node/zone number into the flags. These could be all handled with a small perfect hash table, like the original x86_64 port did, which should be quite cheap to look up. Then there should be enough bits for everyone again. -Andi