Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161191AbWLIPtE (ORCPT ); Sat, 9 Dec 2006 10:49:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030645AbWLIPtE (ORCPT ); Sat, 9 Dec 2006 10:49:04 -0500 Received: from mail.tbdnetworks.com ([204.13.84.99]:42507 "EHLO mail.tbdnetworks.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936995AbWLIPtB convert rfc822-to-8bit (ORCPT ); Sat, 9 Dec 2006 10:49:01 -0500 Subject: Re: Why is "Memory split" Kconfig option only for EMBEDDED? From: Norbert Kiesel To: Alejandro Riveira =?ISO-8859-1?Q?Fern=E1ndez?= Cc: Adrian Bunk , Arjan van de Ven , linux-kernel@vger.kernel.org In-Reply-To: <20061209132742.7a25dcb5@localhost.localdomain> References: <1165405350.5954.213.camel@titan.tbdnetworks.com> <1165406299.3233.436.camel@laptopd505.fenrus.org> <1165407548.5954.224.camel@titan.tbdnetworks.com> <20061206131003.GF24140@stusta.de> <20061209132742.7a25dcb5@localhost.localdomain> Content-Type: text/plain; charset=utf-8 Organization: TBD Networks Date: Sat, 09 Dec 2006 16:45:04 +0100 Message-Id: <1165679105.7455.116.camel@titan.tbdnetworks.com> Mime-Version: 1.0 X-Mailer: Evolution 2.8.1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3690 Lines: 95 On Sat, 2006-12-09 at 13:27 +0100, Alejandro Riveira Fernández wrote: > El Wed, 6 Dec 2006 14:10:03 +0100 > Adrian Bunk escribió: > > > On Wed, Dec 06, 2006 at 01:19:08PM +0100, Norbert Kiesel wrote: > > > On Wed, 2006-12-06 at 12:58 +0100, Arjan van de Ven wrote: > > > > On Wed, 2006-12-06 at 12:42 +0100, Norbert Kiesel wrote: > > > > > Hi, > > > > > > > > > > I remember reading on LKML some time ago that using VMSPLIT_3G_OPT would > > > > > be optimal for a machine with exactly 1GB memory (like my current > > > > > desktop). Why is that option only prompted for after selecting EMBEDDED > > > > > (which I normally don't select for desktop machines > > > > > > > > because it changes the userspace ABI and has some other caveats.... this > > > > is not something you should muck with lightly > > > > > > > > > > Hmm, but it's also marked EXPERIMENTAL. Would that not be the > > > sufficient? Assuming I don't use any external/binary drivers and a > > > self-compiled kernel w//o any additional patches: is there really any > > > downside? > > > > - Wine doesn't work (I'm not sure about VMSPLIT_3G_OPT, but > > VMSPLIT_2G definitely breaks Wine) > > I use VMSPLIT_3G_OPT=y and wine works just fine (only tested with one > program). Edgy + 2.6.19-rc1 > > > > > - AFAIR some people reported problems with some Java programs > > after fiddling with the vmsplit options > > > > EMBEDDED isn't exactly the right way to hide it, but the vmsplit options > > aren't something you can safely change. > > So far all first-hand experiences I heard of were positive (i.e. I did not get an emaail from anyone saying: It had a negative effect for me), so I propose to apply the patch from Con Kolivas. The wording in the description still very strongly recommends to not change that value, and it's still dependent on EXPERIMENTAL. I append the patch just because it's short, it's also available from http://www.kernel.org/pub/linux/kernel/people/ck/patches/2.6/2.6.19/2.6.19-ck2/patches/kconfig-expose_vmsplit_option.patch The options to alter the vmsplit to enable more lowmem are hidden behind the embedded option. Make it more exposed for -ck users and make the help menu more explicit about what each option means. Signed-off-by: Con Kolivas --- arch/i386/Kconfig | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) Index: linux-2.6.19-ck2/arch/i386/Kconfig =================================================================== --- linux-2.6.19-ck2.orig/arch/i386/Kconfig 2006-11-30 11:30:32.000000000 +1100 +++ linux-2.6.19-ck2/arch/i386/Kconfig 2006-12-09 09:01:36.000000000 +1100 @@ -500,7 +500,7 @@ endchoice choice depends on EXPERIMENTAL - prompt "Memory split" if EMBEDDED + prompt "Memory split" default VMSPLIT_3G help Select the desired split between kernel and user memory. @@ -519,14 +519,14 @@ choice option alone! config VMSPLIT_3G - bool "3G/1G user/kernel split" + bool "Default 896MB lowmem (3G/1G user/kernel split)" config VMSPLIT_3G_OPT depends on !HIGHMEM - bool "3G/1G user/kernel split (for full 1G low memory)" + bool "1GB lowmem (3G/1G user/kernel split)" config VMSPLIT_2G - bool "2G/2G user/kernel split" + bool "2GB lowmem (2G/2G user/kernel split)" config VMSPLIT_1G - bool "1G/3G user/kernel split" + bool "3GB lowmem (1G/3G user/kernel split)" endchoice config PAGE_OFFSET - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/