From mboxrd@z Thu Jan 1 00:00:00 1970 Received: by nz-out-0506.google.com with SMTP id f1so998606nzc for ; Sat, 21 Apr 2007 09:32:15 -0700 (PDT) Message-ID: Date: Sat, 21 Apr 2007 09:32:15 -0700 From: "Ulrich Drepper" Subject: Re: [PATCH] lazy freeing of memory through MADV_FREE 2/2 In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <46247427.6000902@redhat.com> <4627DBF0.1080303@redhat.com> <20070420140316.e0155e7d.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org Return-Path: To: Hugh Dickins Cc: Andrew Morton , Rik van Riel , Jakub Jelinek , linux-kernel , linux-mm List-ID: On 4/21/07, Hugh Dickins wrote: > But the Linux MADV_DONTNEED does throw away > data from a PROT_WRITE,MAP_PRIVATE mapping (or brk or stack) - those > changes are discarded, and a subsequent access will revert to zeroes > or the underlying mapped file. Been like that since before 2.4.0. I didn't say it changed. I just say that there is a hole in the current implementation as it does not allow to implement POSIX_MADV_DONTNEED with anything but a no-op. The POSIX_MADV_DONTNEED behavior is useful and something IMO should be added to allow implementing it. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org