Bug 730077

Summary:	kdump: x86: Improve crashkernel=auto logic to take into account memory used by filtering utility
Product:	Red Hat Enterprise Linux 6	Reporter:	Vivek Goyal <vgoyal>
Component:	kernel	Assignee:	Vivek Goyal <vgoyal>
Status:	CLOSED ERRATA	QA Contact:	Chao Ye <cye>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	6.2	CC:	amwang, anderson, cye, dmaley, jburke, jstancek, qcai
Target Milestone:	rc
Target Release:	---
Hardware:	x86_64
OS:	Linux
Whiteboard:
Fixed In Version:	kernel-2.6.32-192.el6	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2011-12-06 14:03:54 UTC	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 Vivek Goyal 2011-08-11 17:38:14 UTC

Description of problem:

crashkernel=auto reserves the memory automatically for a system. Recent profiling of kdump memory showed that on bigger RAM systems we need more kdump RAM because filtering utility needs 2bits of RAM for every physical 4K page. That means on 1TB of memory system, we need 64MB of extra kdump memory just to filter the vmcore.

Fix crashkernel=auto logic to take above into account. This should improve our ability to reserve just right amount of memory on many machines out there.


Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1.
2.
3.
  
Actual results:


Expected results:


Additional info:

Comment 3 RHEL Program Management 2011-08-11 18:10:16 UTC

This request was evaluated by Red Hat Product Management for inclusion
in a Red Hat Enterprise Linux maintenance release. Product Management has 
requested further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed 
products. This request is not yet committed for inclusion in an Update release.

Comment 6 Aristeu Rozanski 2011-08-24 15:54:13 UTC

Patch(es) available on kernel-2.6.32-192.el6

Comment 9 Chao Ye 2011-09-19 01:33:16 UTC

Tested on dell-per910-02.lab.bos.redhat.com with crashkernel=auto and crashkernel=192M:
https://beaker.engineering.redhat.com/recipes/275192

Change status to VERIFIED.

Comment 10 errata-xmlrpc 2011-12-06 14:03:54 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHSA-2011-1530.html