Bug 4530

Summary:	second processor idle
Product:	[Retired] Red Hat Linux	Reporter:	gilmore
Component:	kernel	Assignee:	Cristian Gafton <gafton>
Status:	CLOSED CURRENTRELEASE	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	6.0	CC:	gilmore
Target Milestone:	---
Target Release:	---
Hardware:	i386
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description gilmore 1999-08-15 04:52:39 UTC

Hi,

We installed the SMP kernel from our RH6.0 distribution
onto A DP Pentium Pro system but it seems that only one
one processor is running user processes.

I put two shell loops into background via:

echo 'while : ; do : ; done' | sh &

and then waited for a few seconds and ran top:

21530 gilmore   17   0   804  804   680 R       0 40.6  0.3
  3:27 sh
20224 radha     20   4 92824  90M  1280 R N     0 38.3 36.0
794:13 casim_fast
21518 gilmore   15   0   804  804   680 R       0 28.8  0.3
 15:51 sh


/proc/cpuinfo reports:

processor	: 0
vendor_id	: GenuineIntel
cpu family	: 6
model		: 1
model name	: Pentium Pro
stepping	: 9
cpu MHz		: 199.434997
cache size	: 256 KB
fdiv_bug	: no
hlt_bug		: no
sep_bug		: no
f00f_bug	: no
fpu		: yes
fpu_exception	: yes
cpuid level	: 2
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic
sep mtrr pge mca cmov
bogomips	: 199.07

processor	: 1
vendor_id	: GenuineIntel
cpu family	: 6
model		: 1
model name	: Pentium Pro
stepping	: 9
cpu MHz		: 199.434997
cache size	: 256 KB
fdiv_bug	: no
hlt_bug		: no
sep_bug		: no
f00f_bug	: no
fpu		: yes
fpu_exception	: yes
cpuid level	: 2
wp		: yes
flags		: fpu vme de pse tsc msr pae mce cx8 apic
sep mtrr pge mca cmov
bogomips	: 199.07

Any idea on what could be the cause?

Thanks,

Doug Gilmore
Equator Technologies

Comment 1 Cristian Gafton 1999-08-30 01:59:59 UTC

How can you tell from that that only one processor is being used? A
process can not run on more than one CPU at once; the kernel will
load-balance the CPUs though when new processes are created.