Re: 50% slowdown on 2 processor XEN 4.1.3 vs 1 processor system

[Thor Lancelot Simon <tls%panix.com@localhost>]

On Mon, Nov 26, 2012 at 11:06:37PM -0800, Harry Waddell wrote:
> On Tue, 27 Nov 2012 00:09:32 -0600
> "Cherry G. Mathew" <cherry.g.mathew%gmail.com@localhost> wrote:
> 
> > On 26 November 2012 03:00, Harry Waddell 
> > <waddell%caravaninfotech.com@localhost> wrote:
> > >
> > > I just built a new server with 2 x E5-2630 processors and was comparing 
> > > the
> > > performance to a nearly identical xen server with 1 x E5-1660 processor 
> > > and
> > > found that on a per core basis, instead of being about 50% faster ( as 
> > > one would expect from the clock speed given that the architecture is 
> > > nearly identical ), the E5-1660 system is %300 faster, so I ran some 
> > > benchmarks and started looking for a pattern.

I agree with others in this thread who've suggested there is likely a
system problem that's effectively downclocking the CPUs.  Do the Xen
and NetBSD dom0 dmesg output show anything about CPU clock speed or
power management that looks radically different from the bare-metal
NetBSD case?

Thor