The problem is not SMP, is ACPI. I installed a non-ACPI Hal, but
SMP capable, and the performance went right up with 4 virtual processors.
I hope the developers can look into this mess.
Federico
From: Dirk Utterback
[mailto:dirk.utterback@xxxxxxxxx]
Sent: Sunday, December 28, 2008 9:40 PM
To: Venefax
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
Subject: Re: [Xen-devel] Windows SMP
It seems something
wrong. It is hard to achieve linear performance with more processors, but it
should be at least something "normal". Another choice might be
halsign turbogate drivers. I used it half a year ago, and it is stable and
performance is really nice.
2008/12/27 Venefax <venefax@xxxxxxxxx>
I think that we need to tackle the absurd loss of performance that any
Windows HVM incurs with more than one processor. I have measured it and it is
amazing. I have an application that opens 15 independent network clients, and
with one single processor and the Standard PC Hal, it takes a little over a
minute to load the 15 clients and also to register with the SIP provider. If I
leave that unchanged, I mean "ceteris paribus" , and only change the
HAL to ACPI and add 8 processors, then the same operation takes over 10
minutes. Hello!!! I am using the GPLVL drivers from James Harper. Right now I
am about to test the MPS –Non-ACPI HAL, but the driver still create a BSOD.
Maybe the problem is only ACPI, and not MPS, who knows. In any case, what can
we do so any Windows virtual machine can achieve a "normal"
performance, I mean, a linear performance when using more processors and not
this declining curve that can kill any host.
Federico
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel
