From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.12] helo=sc8-sf-mx2.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1BQX3w-0000w9-5d for user-mode-linux-devel@lists.sourceforge.net; Wed, 19 May 2004 12:49:12 -0700 Received: from smtp1.wanadoo.fr ([193.252.22.30] helo=mwinf0102.wanadoo.fr) by sc8-sf-mx2.sourceforge.net with esmtp (Exim 4.30) id 1BQX3v-0003kx-Gu for user-mode-linux-devel@lists.sourceforge.net; Wed, 19 May 2004 12:49:11 -0700 Subject: Re: [uml-devel] [PATCH] host context switch reduction From: Laurent Vivier In-Reply-To: <018a01c43dd9$0173f270$2000000a@schlepptopp> References: <20040229043549.GA8583@ccure.user-mode-linux.org> <02dc01c43c4a$bb7c0490$2000000a@schlepptopp> <1084831251.1230.4.camel@chartreuse> <03ff01c43c5d$7db6e5e0$2000000a@schlepptopp> <20040518175904.GB29114@ccure.user-mode-linux.org> <1084987654.2250.4.camel@chartreuse> <012201c43dcb$402ca6a0$2000000a@schlepptopp> <1084990661.2255.28.camel@chartreuse> <018a01c43dd9$0173f270$2000000a@schlepptopp> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-1tmBlf+oWRFIHULbKNoc" Message-Id: <1084996157.2256.36.camel@chartreuse> Mime-Version: 1.0 Sender: user-mode-linux-devel-admin@lists.sourceforge.net Errors-To: user-mode-linux-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: The user-mode Linux development list List-Post: List-Help: List-Subscribe: , List-Archive: Date: Wed, 19 May 2004 21:49:18 +0200 To: roland Cc: user-mode-linux-devel@lists.sourceforge.net --=-1tmBlf+oWRFIHULbKNoc Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable In include/linux/ptrace.h , change #define PTRACE_SCEMU 25 by #define PTRACE_SCEMU 31 Le mer 19/05/2004 =E0 21:39, roland a =E9crit : > >OK, as I didn't find skas patch for 2.6 I thought it didn't exist... > there exists one at: > http://www.user-mode-linux.org/~blaisorblade/patches/host-skas3-2.6.6-v1.= patch >=20 > i applied your patch after applying the skas patch. > it applies cleanly - good , > but compile fails very early with the following errormessage: >=20 > arch/i386/kernel/ptrace.c: In function `sys_ptrace': > arch/i386/kernel/ptrace.c:509: error: duplicate case value > arch/i386/kernel/ptrace.c:509: error: previously used here > make[1]: *** [arch/i386/kernel/ptrace.o] Error 1 > make: *** [arch/i386/kernel] Error 2 >=20 > unfortunately, i don`t get this managed to fix myself. > could you (or someone else) take a look ? >=20 > regards > roland >=20 >=20 > ----- Original Message -----=20 > From: "Laurent Vivier" > To: "roland" > Cc: "Jeff Dike" ; > Sent: Wednesday, May 19, 2004 8:17 PM > Subject: Re: [uml-devel] [PATCH] host context switch reduction >=20 >=20 > Le mer 19/05/2004 =E0 20:01, roland a =E9crit : > > Hi Laurent ! > > Great! > > Thanks a lot for your work :) > > > > but i have a question: > > > > old mail from jeff: > > >The patches below are from Laurent Vivier who didn't make them public.= They > > >add a new feature to ptrace on the host which cuts down on the number = of > > >context switches needed for a UML system call, plus makes UML use it > > > > so - if your patch adds a new feature for ptrace on the HOST - shouldn`= t we need TWO patches for 2.6 ? > > One patch for uml and one patch for the host ? > > > > this one seems for uml only. > > some of us already run uml 2.6(.x) on a 2.6.(.x) host and put their foc= us on the "new kernel" (me too). >=20 > OK, as I didn't find skas patch for 2.6 I thought it didn't exist... > anyway I tried to port the 2.4 host sysemu patch to 2.6, find it > attached. I never tested it, or compiled it ! I have no system with 2.6 > kernel, and the only I386 system I have is very, very, very noisy... > it's a good system only when it is switched off ;-) ! >=20 > > regards > > roland > > > > ps: > > since this would be the 2nd patch for the HOST (besides skas), would it= make sense, to merge "skas" and "sysemu" into one common > > HOST-patch (if it has been tested and approved stable) ? > > >=20 > YES, I think... but Jeff is the boss ;-) >=20 > > > > > > ----- Original Message -----=20 > > From: "Laurent Vivier" > > To: "Jeff Dike" > > Cc: "roland" ; > > Sent: Wednesday, May 19, 2004 7:27 PM > > Subject: Re: [uml-devel] [PATCH] host context switch reduction > > > > > > Hi, > > > > as it is a plebiscite ;-), find attached the patch for UML 2.6.6 and > > measurements I made on my poor netserver. > > > > Laurent > > > > Le mar 18/05/2004 =E0 19:59, Jeff Dike a =E9crit : > > > On Tue, May 18, 2004 at 12:22:45AM +0200, roland wrote: > > > > the question is: > > > > is the "real world" performance benefit, uml get`s from this patch = worth taking your time and is it implemented in a way, so > > that > > > > uml maintainers are happy with that ? > > > > > > The patch seems reasonable to me. I'd be happiest with Laurent pushi= ng this > > > into mainline himself. > > > > > > > i cannot really estimate, what performance benefits your patch brin= gs to uml in detail, but what i have seen so far, this > seems > > > > quite worth doing the work. reducing context switches by 1/3 is a = LOT, imho - and reducing the execution time of the > > getpid-loop to > > > > nearly the half is quite impressive. > > > > > > Yeah, but no real workloads do while(1) getpid(); > > > > > > The kernel build improvement is obviously smaller, but still worth ha= ving. > > > > > > > are there any "con`s" that argue for that work _NOT_ being done ? > > > > > > No. But testing, and happy reports to the appropriate mailing lists = would > > > help. > > > > > > Jeff > > > > > > > > -----------------------------------------------------------------------= --------- > > > > > > > HP Netserver LH Pro bi-pro 200 MHz / 256 MB RAM > > > > > > NATIF: > > > > > > netserver:/usr/src# uname -a > > > Linux netserver 2.4.24-sysemu #4 SMP Tue Feb 17 16:43:11 CET 2004 i68= 6 GNU/Linux > > > > > > netserver:/usr/src# time ./getpid 1000000 > > > > > > real 0m1.763s > > > user 0m0.910s > > > sys 0m0.860s > > > > > > real 0m1.759s > > > user 0m0.900s > > > sys 0m0.870s > > > > > > real 0m1.759s > > > user 0m0.950s > > > sys 0m0.800s > > > > > > UML with sysemu: > > > > > > (none):~# uname -a > > > Linux (none) 2.6.6-1um #10 Wed May 19 12:54:37 CEST 2004 i686 unknown > > > > > > (none):/mnt/usr/src# time ./getpid 1000000 > > > > > > real 1m1.508s > > > user 0m7.960s > > > sys 0m53.450s > > > > > > real 1m1.881s > > > user 0m6.630s > > > sys 0m55.240s > > > > > > real 1m1.920s > > > user 0m6.580s > > > sys 0m55.340s > > > > > > UML w/o sysemu > > > > > > real 1m32.833s > > > user 0m7.610s > > > sys 1m25.130s > > > > > > real 1m32.921s > > > user 0m7.890s > > > sys 1m24.980s > > > > > > real 1m33.493s > > > user 0m8.010s > > > sys 1m24.960s > > > > > >=20 --=-1tmBlf+oWRFIHULbKNoc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Ceci est une partie de message =?ISO-8859-1?Q?num=E9riquement?= =?ISO-8859-1?Q?_sign=E9e=2E?= -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (GNU/Linux) iD8DBQBAq7o8bmJwdIv5dzMRAkVvAJ9rh6cdAo69G+MSo3tg7Yt+1z82rwCeM+se K+o2mrjObOrImKwuBiPEen4= =xmuC -----END PGP SIGNATURE----- --=-1tmBlf+oWRFIHULbKNoc-- ------------------------------------------------------- This SF.Net email is sponsored by: SourceForge.net Broadband Sign-up now for SourceForge Broadband and get the fastest 6.0/768 connection for only $19.95/mo for the first 3 months! http://ads.osdn.com/?ad_id=2562&alloc_id=6184&op=click _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel