I believe, from a past conversation, that
disabling hyper-threading on bridgehead servers with lots of inbound
connections, i.e. in enterprise deployments, should be *considered* as
the replication queue has two parallel threads for processor, core or hyper
threading processor as the system call sees all in the same way -multiple
processors. However, there's no real guideline here as there are so many
variables, i.e. amount of change, compression, new objects, mods, whether the
data is in cache or not, etc.
I don't think it matters all that much for
the AD stuff. You might need to look into the FRS side of things (in big
environments). It will matter for CPU-intensive apps that weren't written
directly for multiple-processor systems. Under such circumstances, it is
often recommended to disable hyper threading.
For example, you have to disable HT for
SAP servers. I don't think SQL cares as that is written for multiple-CPU
support and can probably tell the difference between two physical processors and
HT processors but don't know. Like Al said, check the Virtual Server
readme, as NIC teaming isn't supported for the host, apparently (unless, like
AD, that's just load-balanced teaming).
--Paul
----- Original Message -----
Sent: Tuesday, August 08, 2006 2:11
PM
Subject: Re: [ActiveDir] DCs &
Hyper-Threading
From Tim
Mangan's whitepaper on hyperthreading under 2003: "The results in this paper are exclusively related to
Windows Server 2003. We are currently running the tests used in the
development of this paper under erver 2000. We can verify reports of performance and stability problems with
Hyper-Threading on Windows 2000 Server, and at this time recommend customers
disable Hyper-Threading under 2000." http://www.tmurgent.com/images/WP_HyperThread.pdf
So disable under 2000 is the recomendation, As to 2003
he shows a small performance increase in all cases except multithreaded
CPU-bound applications, which is expected. Personally I leave hyperthreading
turned on for my 2003 installs. It also makes single->dual cpu upgrades
easier since the SMP kernal is already used =)
Thanks, Andrew
Fidel
"Wyatt, David"
<[EMAIL PROTECTED]> Sent
by: [EMAIL PROTECTED]
08/07/2006 09:45 AM
Please respond
to ActiveDir@mail.activedir.org |
|
To
| <ActiveDir@mail.activedir.org>
|
cc
|
|
Subject
| [ActiveDir] DCs &
Hyper-Threading |
|
What are people's views on whether to enable or disable hyper-threading
on a Proliant box running Windows 2003 as a DC. I remember Intel advised
HT to be disabled on Windows 2000 but has this changed for Windows 2003?.
Are the performance benefits significant for a DC? Thanks David **************************************************************************** This message contains confidential
information and is intended only for the
individual or entity named. If you are not the named addressee you should not disseminate,
distribute or copy this e-mail. Please
notify the sender immediately by e-mail if you have received this e-mail by mistake and delete this e-mail from your
system. E-mail
transmission cannot be guaranteed to be secure or error-free as information could be
intercepted, corrupted, lost, destroyed, arrive
late or incomplete, or contain viruses. The
sender therefore does not accept liability for any errors or omissions in the contents of this
message which arise as a result of e-mail
transmission. If verification is required
please request a hard-copy version. This message is provided for informational purposes and
should not be construed
as an invitation or offer to buy or sell any securities or
related financial instruments. GAM operates in many jurisdictions
and is regulated or licensed in those
jurisdictions as required. ****************************************************************************
|