Bug 5588

Summary:	Use CONFIG_SLAB=y instead of CONFIG_SLUB=y at least for server flavour
Product:	Mageia	Reporter:	Frederik Himpe <fhimpe>
Component:	RPM Packages	Assignee:	Thomas Backlund <tmb>
Status:	RESOLVED FIXED	QA Contact:
Severity:	enhancement
Priority:	Normal	Keywords:	NEEDINFO
Version:	Cauldron
Target Milestone:	---
Hardware:	x86_64
OS:	Linux
Whiteboard:
Source RPM:	kernel	CVE:
Status comment:

Description Frederik Himpe 2012-04-24 15:16:04 CEST

For the server kernel flavour, you want to use SLAB instead of SLUB. I noticed that Debian had SLAB instead of SLUB, and I asked on irc://irc.debian.org/#debian-irc kernel why: apparently SLUB is not efficient on NUMA systems, which is the case for most current multi-core/multi-socket CPU's.

Debian changelog for linux-2.6 2.6.39-1:
http://packages.qa.debian.org/l/linux-2.6/news/20110520T191047Z.html

"   * mm: Select SLAB allocator again. Although SLUB is currently the
     upstream default, this was set as an experiment rather than a
     recommendation! SLUB generally has poorer performance than SLAB on
     larger systems."


According to this bug report, Red Hat Enterprise Linux is also using SLAB by default:
https://bugzilla.redhat.com/show_bug.cgi?format=multiple&id=443962

Manuel Hiebel 2012-04-25 00:29:06 CEST

Assignee: bugsquad => tmb

Comment 1 Marja Van Waes 2012-05-26 13:07:44 CEST

Hi,

This bug was filed against cauldron, but we do not have cauldron at the moment.

Please report whether this bug is still valid for Mageia 2.

Thanks :)

Cheers,
marja

Keywords: (none) => NEEDINFO

Comment 2 Thomas Backlund 2012-06-01 15:20:01 CEST

tmb <tmb> 3.3.6-1.mga2:
+ Revision: 235512
- switch server kernels back to SLAB allocator as it performs better on
  bigger server hardware and workloads


I forgot to reference this bug, sorry.

Status: NEW => RESOLVED
Resolution: (none) => FIXED