From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4640906B.2020301@redhat.com> Date: Tue, 08 May 2007 10:59:55 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [PATCH] MM: implement MADV_FREE lazy freeing of anonymous memory References: <4632D0EF.9050701@redhat.com> <463B108C.10602@yahoo.com.au> <463B598B.80200@redhat.com> <463BC62C.3060605@yahoo.com.au> <463E5A00.6070708@redhat.com> <464014B0.7060308@yahoo.com.au> In-Reply-To: <464014B0.7060308@yahoo.com.au> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Nick Piggin Cc: Ulrich Drepper , Linus Torvalds , linux-kernel , linux-mm , Andrew Morton , Jakub Jelinek List-ID: Nick Piggin wrote: > We have percpu and cache affine page allocators, so when > userspace just frees a page, it is likely to be cache hot, so > we want to free it up so it can be reused by this CPU ASAP. > Likewise, when we newly allocate a page, we want it to be one > that is cache hot on this CPU. Actually, isn't the clear page function capable of doing some magic, when it writes all zeroes into the page, that causes the zeroes to just live in CPU cache without the old data ever being loaded from RAM? That would sure be faster than touching RAM. Not sure if we use/trigger that kind of magic, though :) -- Politics is the struggle between those who want to make their country the best in the world, and those who believe it already is. Each group calls the other unpatriotic. -- 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