From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Theurer Subject: Re: 46% performance drop with change in glibc Date: Tue, 08 Nov 2005 07:05:49 -0600 Message-ID: <4370A2AD.1070803@us.ibm.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Ian Pratt Cc: xen-devel@lists.xensource.com, Ulrich Drepper , Robert Read List-Id: xen-devel@lists.xenproject.org Ian Pratt wrote: >>>>The crippled ABI is supported by the code in /lib/i686/nosegneg. >>>>This code is *automatically* used if the kernel is >>>> >>compiled to match >> >>>>the glibc version. This happens using the >>>> >>>>linux-2.6-xen-vdso-note.patch >>>> >>>I believe we have this patch in the xen repo, but I haven't ever >>>verified whether the right thing happens under FC4. >>> >>I am not seeing this patch in ./patches/linux-2.6.12 >>directory. Is it somewhere else? >> > >It should be in the main tree. The appended patch was included some time >ago, but I've never tested it to see whether it works since I don't >generally run bleeding edge Fedora. > >Is there some piece of the patch missing? > No, it's all there. Only part I needed was the change to ld.so.conf. So, anyone with FC4, you might want to make sure you have the entry "hwcap 0 nosegneg". It looks like the performance regression has disappeared now. Thanks all for you help. -Andrew