> > > > AFAIK KVM will always emulate CPUs not cores. > > > In fact, newer qemu/kvm supports "cores" parameter when used > with smp: > https://patchwork.kernel.org/patch/33961/ > > RHEL6 beta has new kvm and qemu - it is possible to use > multi-core CPU within virtualized winXP there. > > Regards, > > Nenad > I did mean cores not CPU's. I am using Xeon W3520 (4 Core 2.67Ghz). Under Virtualbox, WinXP guest has no problem using all four cores with same Xeon W3520 computer. So far this appears to be limitation of KVM/Virtio drives with XP guests. It does not appear to be KVM limitation since liveCD boot instead of XP.img boot shows 4 cores. I'm really only wanted confirmation that limitation can NOT be worked around. While Virtualbox did not have this issue, it had other problems which made KVM a better solution. Running this under Windows 2003 server is also an option if it eliminates the 4 core problem. Marcelino Mata Engineering Technology Specialist Multimatic Technical Centre 85 Valleywood Drive Markham, ON Canada L3R 5E5 Tel. +1 905 470 0025 CONFIDENTIALITY NOTE: This email (and attachments, if any) contain(s) information that is PRIVATE and CONFIDENTIAL, and may be LEGALLY PRIVILEGED or otherwise exempt from disclosure under applicable law. All copyright is reserved, and no right or license is granted to duplicate or publish the content of this email or to forward it to third parties, without, in each case, specific permission. If you have received this email in error, you must not copy, distribute, retain or use this email or the information contained in it for any purpose (other than to notify the sender). If you believe that you are not the intended recipient of this email, please contact the sender immediately and delete this email from your computer system (including any archive or other storage facilities). Thank you.