From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262814AbUDHV7g (ORCPT ); Thu, 8 Apr 2004 17:59:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262788AbUDHV7g (ORCPT ); Thu, 8 Apr 2004 17:59:36 -0400 Received: from fmr06.intel.com ([134.134.136.7]:6086 "EHLO caduceus.jf.intel.com") by vger.kernel.org with ESMTP id S262730AbUDHV7e convert rfc822-to-8bit (ORCPT ); Thu, 8 Apr 2004 17:59:34 -0400 content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT X-MimeOLE: Produced By Microsoft Exchange V6.0.6487.1 Subject: RE: HUGETLB commit handling. Date: Thu, 8 Apr 2004 14:58:40 -0700 Message-ID: <01EF044AAEE12F4BAAD955CB75064943014B92FA@scsmsx401.sc.intel.com> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: HUGETLB commit handling. Thread-Index: AcQdkJmYwmNjBCE1RyiI8vJes+zUXwAI5UBg From: "Seth, Rohit" To: "Andy Whitcroft" , "Andrew Morton" , "Chen, Kenneth W" , "Ray Bryant" Cc: "Martin J. Bligh" , , , , , , X-OriginalArrivalTime: 08 Apr 2004 21:58:41.0272 (UTC) FILETIME=[A7617F80:01C41DB4] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andy Whitcroft <> wrote on Thursday, April 08, 2004 9:36 AM: > We have been looking at the HUGETLB page commit issue (offlist) and > are close a final merged patch. However, our testing seems to have > thrown up an inconsistency in interface which we are not sure whether > to fix or not. > > With normal shm segments we commit the pages we will need at shmget() > time. > The real pages being allocated on demand. With hugetlb pages we > currently do not manage commit, but allocate them on map, shmat() in > this case. When we add commit handling it would seem most > appropriate to commit the pages in shmget() as for small page > mappings. However, this might seem to change the semantics slightly, > in that if there is insufficient hugepages available then the failure > would come at shmget() and not shmat() time. > > I would contend this is the right thing to do, as it makes the > semantics of hugepages match that of the existing small pages. We > are looking for a consensus as this might be construed as a semantic > change. > IMO, doing this accounting check at shmget time seems reasonable as it aligns the accouting semantics of normal and hugepages. > Thoughts. > > -apw > > > - > To unsubscribe from this list: send the line "unsubscribe linux-ia64" > in the body of a message to majordomo@vger.kernel.org More majordomo > info at http://vger.kernel.org/majordomo-info.html