[cod] Linux beta server problems

Jeremiah Gilbert jagged at vtnetworks.net
Sat Oct 29 17:59:07 EDT 2005


I think you're mistaken, as this is a HyperTransport board, not 
Hyperthreading (hyperthreading is an Intel technology, HyperTransport is 
an AMD technology.. and they are very different techs at that). They 
aren't virtual cpus, but logical cpus.

Intel P4/Xeons use Hyperthreading (which show up as logical cpus as well).
Opteron based boards are HyperTransport, and dont support Hyperthreading.

It sounds like you have 4 dual core processors (so you have a total of 8 
Logical, but very real processors). Very nice rig.. Wish it were mine :)

A Quad Dual Core Xeon would show up w/ 16 logical processors (8 very 
real processors and 8 very virtual hyperthreading units).

Just don't want anyone getting confused!

-Jeremiah


On Sat, 29 Oct 2005, Mark J. DeFilippis wrote:

>
> Yea, I see that people misunderstand this quite a bit....
>
> No, I have a Quad CPU Tyan k8qs-4880 which has 4 Opteron
> CPU's. This is a Hyper Threading motherboard and shows
> up as 8 virtual CPU's.  You can disable processors on the board.
> These Tyan MoBo's are a hidden little secret. The throughput increase
> between CPU/Cache, Bus and memory through HT is the best
> thing since sliced bread. (I picked up on these when Jay mentioned
> them about a year ago, and when I saw this board,I fell in love
> with it.)
>
> The other machine is a Totalcontrol Dual P4 3.2GhZ Proc
> with 2GB Ram at theplanet.com. I will get that one going, but
> it will take more time due to location, and I am only 1 resource.
> That box running RHES 2.4 with 2 3.2P4 HT is dual CPU with
> 4 virtuals per the 2.6SMP Kernel.
>
> To get similar results I can disable 2 CPU's and it runs close
> to the Dual CPU P4... (A little better actually,  because the HT
> CPU's code even in 2.6 SMP Kernel is not all that efficient when
> compared to throughput increases on the Tyan MOBO with HT Bus...
>
> Mark
>
>
>
> At 04:31 PM 10/29/2005, you wrote:
>> Are you thinking a Dual P4 3.2 as a 4 cpu box i.e. HT "cpu's" as
>> real if so you'll be disappointed.
>> 
>> Yes unfortunately a 2.6 P4 is now a low end machine. 4Gb or ram
>> is not really going to help much apart from being a quite expensive
>> disk cache. Servers use upto about 300Mb so by the time you've
>> used all your ram your CPU is crying in most cases.
>>
>>     Steve / K
>
> S1,-------------------------------------------------------------------------------
> Mark J. DeFilippis Ph. D EE           defilm at acm.org
>                                      defilm at ieee.org
>
>
>

-- 
Jeremiah Gilbert aka |VTN|[Jagged]
VTNetworks Server Admin
support at vtnetworks.net
http://www.vtnetworks.net



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