Re: [Qemu-devel] Xenoppix (KNOPPIX5.1.1 + Xen3.0.4 + QEMU/KVM + HTTP-FUSE) is released

[Kuniyasu Suzaki]

Hello.

Thank you for your quick response. We are just trying qemu 0.9.0.

 >>From: Fabrice Bellard <address@hidden>
 >>Subject: Re: [Qemu-devel] Xenoppix (KNOPPIX5.1.1 + Xen3.0.4 + QEMU/KVM + 
 >>HTTP-FUSE) is released
 >>
 >>Kuniyasu Suzaki wrote:
 >>> Dear,
 >>> 
 >>> We released new Xenoppix which is consisted of KNOPPIX5.1.1, Xen3.0.4, 
 >>> QEMU/KVM, 
 >>> and HTTP-FUSE(stackable/network virtual disk). You can compare Xen(3.0.4 
 >>> on Linux2.6.16) 
 >>> and KVM(Release 12 on Linux2.6.19) on the CD-ROM.

I forgot telling our project home page.
  http://unit.aist.go.jp/itri/knoppix/xen/index-en.html

 >>> [...]
 >>> ### Performance 
 >>>  -PI calculation(3 Million-digits) is used to compare. 
 >>>     http://h2np.net/pi/pi_quick_start.tar.gz
 >>>   We confirmed the performance of kvm was very close to native CPU. 
 >>> However the I/O
 >>>   was still slow.
 >>>                | sec   |
 >>>     -----------+-------+----------------------------
 >>>      Native CPU| 14.67 | Core2 Duo (T7200)
 >>>             kvm| 17.90 | IntelVT is effective
 >>>        kvm(off)| 225.1 | "-no-kvm" is used
 >>>     qemu(kqemu)| 24.87 | "-kernel-kqemu" isn't used
 >>>            qemu| 227.1 | "-no-kqemu" is used
 >>>       Xen(DomU)| 14.68 |
 >>>        Xen(HVM)| 15.99 | IntelVT is effective
 >>>     -----------+-------+---------------------------
 >>
 >>Hi,
 >>
 >>Since your benchmark involve a mostly user task, the performance of 
 >>kqemu must be very close to native CPU time. I suggest you make the 
 >>following tests to improve your benchmarking of qemu/kqemu:
 >>
 >>1) Do not use the clock of the virtualized OS to make the measure. QEMU 
 >>may have bugs which make it very inaccurate.

O.K. We will use a physical stopwatch to compare the performance.
The accuracy will be decreased but the fairness will be increased.

 >>2) For best performances with kqemu, it is better to use Linux 2.4 as 
 >>guest OS (I know this is far from acceptable, but it can help some 
 >>people to get better performance !).

Please tell me the reason why Linux 2.4 shows better performance, if
you have time. Does the difference of clock tick cause the problem?

------
suzaki