Andrew,
Not sure if this applies here, but
here is Microsoft stance on Hyperthreading CPU's...
Microsoft says...
Per Processor Licensing
For
currently available Microsoft servers products licensed on a per processor
basis (e.g., Microsoft SQL Server™, Microsoft BizTalk Server™, Microsoft
Content Management Server™, etc.), one processor license for each physical
processor on the server is required. Therefore, customers only need to acquire
one processor license for each physical HTT even though the software may count
one HTT as two logical processors.
See the full deal
at:
http://www.microsoft.com/licensing/downloads/hyper_threading.doc
Keith
I've
no comment to offer on the suitability of flavour of Windows 2003 for IMail,
but I can comment on how the Hyperthreading is treated.
On
all Windows 2003 servers with hyperthreading enabled, you will see double the
number of physical CPUs in the Task Manager, in the Device Manager, and in
WinMSD. This lets applications see 4 CPUs on a dual server.
However for thread scheduling and for licencing the OS, the HAL (Hardware
Abstraction Layer) knows which ones are the physical CPUs and which are the
virtual CPUs.
Windows 2000 servers do not have that distinction, and Microsoft will
not back-port the logic from W2K3 to W2K. W2K sees hyperthreading
virtual CPUs as physical CPUs, so you would get into licencing issues if the
number of CPUs exceeds your licence.
You
would also get into performance issues because Microsoft simply uses the first
CPUs it sees and ignores the ones that exceed your licence; as the order of
discovery is physical, virtual, physical, virtual... you end up using half
physical and half virtual CPUs, when what you want are only the CPUs that
are physical to fit in your licence constraint. Therefore, if you have a
licencing problem with W2K, either upgrade to W2K3 or turn off
hyperthreading.
Andrew 8)
After
watching things run for a couple of weeks on Windows 2003 Server, I have
concluded that my IMail/Declude setup is running +30% more efficiently than
it did on Windows 2000. Because of this, I am thinking of getting rid
of my Windows 2000 installations and replacing them with Windows
2003.
I haven't noted much discussion around here regarding Windows
2003 Web Edition as a suitable host for IMail/Declude. From
what I have read, I don't believe there are any limitations that would
prevent this setup from running properly, though I'm not yet positive at
this point. Here is a link to the matrix that Microsoft has
published:
http://www.microsoft.com/windowsserver2003/evaluation/features/compareeditions.mspx
The
only thing that stands out is the limitations to 2-Way SMP whereas Standard
Edition supports 4-Way SMP. I'm not sure if dual hyperthreaded
processors are the equivalent of 2- or 4-Way SMP. Maybe someone could
offer up some knowledge there. Even if so, the hyperthreading can be
disabled, and I'm not convinced that having 4 processors/instances is
beneficial to the environment.
I also know that MS SQL server can't
be run on Web Edition, but that isn't an issue here. All of the other
things that it says it won't support are things that I would have disabled
anyway.
So does anyone here have any experience with Web Edition and
the limitations, and have an opinion about whether or not this would work
with an IMail/Declude setup (or for that matter another E-mail platform
since IMail will soon enough be 86'd).
Thanks,
Matt
--
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MailPure custom filters for Declude JunkMail Pro.
http://www.mailpure.com/software/
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