[NTLUG:Discuss] 2 Xeons look like 4

[Jack Snodgrass]

On Tue, 2003-12-23 at 22:12, kbrannen at gte.net wrote:
> Thomas Cameron wrote:
> > ----- Original Message ----- 
> > From: "Bishop, Cass" <cbishop at atxna.com>
> > To: "'NTLUG Discussion List'" <discuss at ntlug.org>
> > Sent: Tuesday, December 23, 2003 1:02 PM
> > Subject: [NTLUG:Discuss] 2 Xeons look like 4
> > 
> > 
> > 
> >>I have 2 Intel Xeon processors in my server.  When I run top it says there
> >>are 4 cpu's.  Any idea why?  I see this in RedHat 7.3 and RedHat
> > 
> > Enterprise
> > 
> >>Server 3.
> 
> > 
> > Welcome to the world of HyperThreading.  Basically each physical processor
> > runs two virtual instances of itself, in theory giving the computer more
> > oomf.  We use only HT procs at my job, and I love them.  It seems to work
> > pretty darned well.
> 
> Hmm, you're having better luck than I then.  We tried it on RH9.0 on a Compaq 
> DL380 (G3 model w/ dual Xeons) and I found weird stability problems.  The 
> problems all went away when I turned off hyperthreading in the BIOS.
> 
> Kevin


I've got 4 boxes with HT processors ( 2 are dual 2.0GHZ XEONs and 2 are
800MHZ P4 CPUS ) all running just fine with RH 9.0. 

jack