From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751262Ab3F1FHR (ORCPT ); Fri, 28 Jun 2013 01:07:17 -0400 Received: from mail-pd0-f174.google.com ([209.85.192.174]:48404 "EHLO mail-pd0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750814Ab3F1FHP (ORCPT ); Fri, 28 Jun 2013 01:07:15 -0400 Date: Thu, 27 Jun 2013 22:07:12 -0700 From: Anton Vorontsov To: Andrew Morton Cc: Minchan Kim , Luiz Capitulino , linux-mm@kvack.org, linux-kernel@vger.kernel.org, mhocko@suse.cz, kmpark@infradead.org, hyunhee.kim@samsung.com Subject: Re: [PATCH v2] vmpressure: implement strict mode Message-ID: <20130628050712.GA10097@teo> References: <20130626231712.4a7392a7@redhat.com> <20130627150231.2bc00e3efcd426c4beef894c@linux-foundation.org> <20130628000201.GB15637@bbox> <20130627173433.d0fc6ecd.akpm@linux-foundation.org> <20130628005852.GA8093@teo> <20130627181353.3d552e64.akpm@linux-foundation.org> <20130628043411.GA9100@teo> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20130628043411.GA9100@teo> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 27, 2013 at 09:34:11PM -0700, Anton Vorontsov wrote: > ... we can add the strict mode and deprecate the > "filtering" -- basically we'll implement the idea of requiring that > userspace registers a separate fd for each level. Btw, assuming that more levels can be added, there will be a problem: imagine that an app hooked up onto low, med, crit levels in "strict" mode... then once we add a new level, the app will start missing the new level events. In the old scheme it is not a problem because of the >= condition. With a proper versioning this won't be a problem for a new scheme too. Anton