From mboxrd@z Thu Jan 1 00:00:00 1970 From: Con Kolivas Subject: Re: [PATCH] mm: limit lowmem_reserve Date: Sat, 8 Apr 2006 11:01:04 +1000 References: <200604021401.13331.kernel@kolivas.org> <200604081015.44771.kernel@kolivas.org> <443709F1.90906@yahoo.com.au> In-Reply-To: <443709F1.90906@yahoo.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200604081101.06066.kernel@kolivas.org> Sender: owner-linux-mm@kvack.org Return-Path: To: Nick Piggin Cc: Andrew Morton , ck@vds.kolivas.org, linux list , linux-mm@kvack.org List-ID: On Saturday 08 April 2006 10:55, Nick Piggin wrote: > Con Kolivas wrote: > > On Friday 07 April 2006 22:40, Nick Piggin wrote: > >>How would zone_watermark_ok always fail though? > > > > Withdrew this patch a while back; ignore > > Well, whether or not that particular patch isa good idea, it > is definitely a bug if zone_watermark_ok could ever always > fail due to lowmem reserve and we should fix it. Ok. I think I presented enough information for why I thought zone_watermark_ok would fail (for ZONE_DMA). With 16MB ZONE_DMA and a vmsplit of 3GB we have a lowmem_reserve of 12MB. It's pretty hard to keep that much ZONE_DMA free, I don't think I've ever seen that much free on my ZONE_DMA on an ordinary desktop without any particular ZONE_DMA users. Changing the tunable can make the lowmem_reserve larger than ZONE_DMA is on any vmsplit too as far as I understand the ratio. -- -ck -- 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