lkml.org 
[lkml]   [2007]   [Jan]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectIntel Core Duo/Duo2 T2300/E6400 - Hyper-Threading (the absence of)
(Please CC me, I am not subscribed to LKML [I have set the
Mail-Followup-To header accordingly]).

On two of my new machines, with Intel Core Duo T2300 and Core2 Duo E6400
chips respectively, I noticed some weirdness in how many CPUs are
present.

If the hyper-threading bit is present in the CPU info, should there
always be a an extra CPU presented to the system per physical core?

Both the Core1 and Core2 chips I have the ht bit set, but present only
their two physical cores to the system. No access to the hyper-threading
capabilities at all. I also see no configuration options in the BIOS to
enable or disable hyper-threading. That is, /proc/cpuinfo and all
topology data only shows 2 CPUs present, and that they are not the HT
pair.
(CONFIG_NR_CPUS=8 is set).

(This was originally triggered by somebody else's code that read the CPU
flags, saw hyper-threading, and decided there were 2x cpus for each
physical core. Said code has already been taken out back and shot
repeatedly).

--
Robin Hugh Johnson
Gentoo Linux Developer
E-Mail : robbat2@gentoo.org
GnuPG FP : 11AC BA4F 4778 E3F6 E4ED F38E B27B 944E 3488 4E85
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2007-01-08 10:53    [W:0.098 / U:0.112 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site