From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <413AE6E7.5070103@yahoo.com.au> Date: Sun, 05 Sep 2004 20:13:59 +1000 From: Nick Piggin MIME-Version: 1.0 Subject: Re: [RFC][PATCH 0/3] beat kswapd with the proverbial clue-bat References: <413AA7B2.4000907@yahoo.com.au> <20040904230210.03fe3c11.davem@davemloft.net> <413AAF49.5070600@yahoo.com.au> In-Reply-To: <413AAF49.5070600@yahoo.com.au> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Nick Piggin Cc: "David S. Miller" , akpm@osdl.org, torvalds@osdl.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: Nick Piggin wrote: > David S. Miller wrote: > >> On Sun, 05 Sep 2004 15:44:18 +1000 >> Nick Piggin wrote: >> >> >>> So my solution? Just teach kswapd and the watermark code about higher >>> order allocations in a fairly simple way. If pages_low is (say), 1024KB, >>> we now also require 512KB of order-1 and above pages, 256K of order-2 >>> and up, 128K of order 3, etc. (perhaps we should stop at about order-3?) >> >> >> >> Whether to stop at order 3 is indeed an interesting question. >> >> The reality is that the high-order allocations come mostly from folks >> using jumbo 9K MTUs on gigabit and faster technologies. On x86, an >> order 2 would cover those packet allocations, but on sparc64 for example >> order 1 would be enough, whereas on a 2K PAGE_SIZE system order 3 would >> be necessary. >> > > Yeah I see. > Hmm, and the crowning argument for not stopping at order 3 is that if we never use higher order allocations, nothing will care about their watermarks anyway. I think I had myself confused when that question in the first place. So yeah, stopping at a fixed number isn't required, and as you say it keeps things general and special cases minimal. -- 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: aart@kvack.org