Since I'm trying to optimize Gentoo on XenServer (as DomU, *not* Dom0), I think this question is best addressed to gentoo-server list.
When I was emerging glibc, I got this warning: * You are using Xen but don't have -mno-tls-direct-seg-refs in your CFLAGS. * This will result in a 50% performance penalty when running with a 32bit * hypervisor, which is probably not what you want. A google-fu brought me to this page: http://cs.felk.cvut.cz/~vaclam1/linux/ucebna/k310/data/doc/howto-xen-and-gentoo-en.html#Before_we_begin There, it mentions 2 things to be done: * -mno-tls-direct-seg-refs in CFLAGS * USE=nptlonly for sys-libs/glibc -- which I assume has been superseded with the global USE=nptl Now my questions: 1. When do we use either (or both)? 1a. I'm compiling Gentoo x86 on XenServer running on an x86-64 (Intel) system, do I need them? 1b. I'm compiling Gentoo amd64 on XenServer running on an x86-64 (Intel) system, do I need them? 1c. Like (1a), but after completion, I'll migrate the VM onto a XenServer running on a Pentium4 system (32-bit), do I need them? (In other words, it's built on top of an x86-64 physical platform, but will be running on top of an x86 physical platform) TIA for your assistance. Rgds, -- Pandu E Poluan ~ IT Optimizer ~ Visit my Blog: http://pepoluan.posterous.com
