Yeak,
The 4 processors are ok. The latest Xeon and Pentium 4 processors have a technology called Hyperthreading . Using it , each processor works to the OS as being two logical processors... This explains the 2 "extra" processors you see...
To disable this , you have to disable Hyperthreading in the bios or disabling ACPI in the kernel... ( I found out that ACPI has to be enabled to make the kernel recognize the virtual CPU when compiling a kernel to a Xeon machine we bought recently). Some tests show this should be disabled in linux , because this leads to some performance penalties , but I'm leaving it enabled anyway...
Pedro Macedo
Message: 29 To: fedora-list@xxxxxxxxxx From: Yeak Nai Siew <yeak@xxxxxxxxx> Subject: Dual processor but see Quad processor Date: Fri, 5 Dec 2003 09:53:06 +0800 Reply-To: fedora-list@xxxxxxxxxx
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Hi all,
I installed Fedora Core 1 on IBM eServer with the following spec: - 1U - 2 x 36 GB Hardware RAID 1 (LSI and driver used is mpt) - 2 x 2.8 Ghz Xeon - 4 x 1 GB RAM
Right after install and logged in, the Gnome desktop seems unstable. Clicking the menu will occasionally paused for 1 or 2 seconds. I left it idle and not touching it, but it crashed automatically. Message log shows gdm-binary having problem. Not sure if it is so.
Then I run "top" and I notice it shows 4 CPU. I know this server only have 2. None of this 4 CPU shows any status. Idle is "0%". The status is wrong.
Then I tried RHEL AS 3, looks more stable, but the "top" also show 4 CPU. This time it shows the figure. Idle is around 98% to 100%. But the status run across all the 4 CPU (the physical CPU is only 2...)
Why seeing 4, not 2? Is there a way to pass kernel parameter during bootup to force it to use 2 only?
Thanks.
-- Yeak Nai Siew << Mac OS Forever >> << Linux Forever>> >>> http://www.redhat.com/rhce/rhce806200928901893.html <<<
