Bug 440281 - NR_CPUS limit of 8 reached
Summary: NR_CPUS limit of 8 reached
Alias: None
Product: Red Hat Enterprise Linux 4
Classification: Red Hat
Component: kernel   
(Show other bugs)
Version: 4.6
Hardware: x86_64 Linux
Target Milestone: rc
: ---
Assignee: Peter Martuccelli
QA Contact: Martin Jenner
Depends On:
TreeView+ depends on / blocked
Reported: 2008-04-02 16:17 UTC by rross
Modified: 2012-06-20 16:09 UTC (History)
0 users

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of:
Last Closed: 2012-06-20 16:09:28 UTC
Type: ---
Regression: ---
Mount Type: ---
Documentation: ---
Verified Versions:
Category: ---
oVirt Team: ---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---

Attachments (Terms of Use)
output in messages file limiting to 8 processors (212.77 KB, image/jpeg)
2008-04-02 16:17 UTC, rross
no flags Details

Description rross 2008-04-02 16:17:54 UTC
Description of problem: I just purchased a Dell R900 server and installed Red
Hat Linux Enterprise 4.6 (EMT64T) and updated the kernel to 2.6.9-67.0.7.ELsmp
x86_64 version.  This server has 4 quad-core processors (E7320).  When I boot
the system, it shows that I have 8 processors of the 16 processors running.  In
/var/log/messages in the boot process descriptions, I see the message "WARNING:
NR_CPUS limit of 8 reached. Processor ignored." while the processors are being
configured.  Why is this version limiting the number of processors to 8 and how
do I get all 16 processors operating?

Version-Release number of selected component (if applicable):
Red Hat Enterprise Linux AS, Release 4 update 6
2.6.9-67.0.7.ELsmp #1 SMP Wed Feb 27 04:47:23 EST 2008 x86_64 x86_64 x86_64

How reproducible:
Every time the system is booted up

Steps to Reproduce:
1. Simply boot the system
Actual results:
limit of 8 processors

Expected results:
all 16 processors should be active

Additional info:

Comment 1 rross 2008-04-02 16:17:55 UTC
Created attachment 300090 [details]
output in messages file limiting to 8 processors

Comment 2 Peter Martuccelli 2008-04-02 16:46:29 UTC
You need to run the largesmp kernel for systems with > 8 cpus on x86_64 in RHEL
4, (install kernel-largesmp-2.6.9-67.EL.x86_64.rpm).  The largesmp x86_64 kernel
supports up to 64 cpus.  Install the largesmp kernel and you will see all 16 cpus.

Comment 3 Jiri Pallich 2012-06-20 16:09:28 UTC
Thank you for submitting this issue for consideration in Red Hat Enterprise Linux. The release for which you requested us to review is now End of Life. 
Please See https://access.redhat.com/support/policy/updates/errata/

If you would like Red Hat to re-consider your feature request for an active release, please re-open the request via appropriate support channels and provide additional supporting details about the importance of this issue.

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