Bug 1434013

Summary:	[downstream clone - 3.6.11] Disable overcommit by default when creating new cluster
Product:	Red Hat Enterprise Virtualization Manager	Reporter:	rhev-integ
Component:	ovirt-engine	Assignee:	Martin Sivák <msivak>
Status:	CLOSED ERRATA	QA Contact:	Artyom <alukiano>
Severity:	medium	Docs Contact:
Priority:	unspecified
Version:	3.6.10	CC:	dfediuck, eheftman, lsurette, mavital, mgoldboi, rbalakri, Rhev-m-bugs, srevivo, ykaul
Target Milestone:	ovirt-3.6.11	Keywords:	Triaged, ZStream
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Release Note
Doc Text:	Previously it was possible to configure memory overcommit without configuring memory ballooning or Kernel Same-page Merging (KSM). This created a scheduling problem as the Manager calculated memory which had not been freed. In this update, by default, memory ballooning and KSM are disabled by default in new clusters and memory overcommit is set to 100% (no overcommit).	Story Points:	---
Clone Of:	1433961	Environment:
Last Closed:	2017-05-09 17:04:14 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	SLA	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description rhev-integ 2017-03-20 14:33:36 UTC

+++ This bug is a downstream clone. The original bug is: +++
+++   bug 1433961 +++
======================================================================

Description of problem:

Currently new clusters have ballooning and KSM disabled by default and overcommit set to 200% by default.

Configuring overcommit without ballooning or KSM does not make any sense. It will affect scheduling (the engine will think it has more memory), but nothing will actually free the memory.

A recent change introduced a check for this situation, but we forgot to change the default value.

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

3.6.11, 4.1.2 and master branch as of 20th of March

How reproducible:

Always

Steps to Reproduce:
1. Create a cluster using REST API providing only name

Actual results:

407 Conflict - it is not possible to enable overcommit without ballooning or KSM

Expected results:

OK - cluster created with all ballooning, KSM and overcommit disabled

Additional info:

We tested a workaround using Python SDK to verify a cluster can be created when the overcommit value is provided:

https://gerrit.ovirt.org/#/c/74303/1

(Originally by Martin Sivak)

Comment 5 Artyom 2017-03-29 10:55:43 UTC

Checked on rhevm-3.6.11-0.1.el6.noarch

Send POST request to the engine:
<cluster>
    <name>overcommit-mburman</name>
    <cpu id="Intel Conroe Family"/>
    <data_center id="00000001-0001-0001-0001-0000000002e0"/>
    <version major="3" minor="6"/>
</cluster>


Response:
<fault>
<reason>Operation Failed</reason>
<detail>[KSM or balooning must be enabled to allow memory optimization.]</detail>
</fault>

Comment 6 rhev-integ 2017-04-07 14:10:12 UTC

INFO: Bug status wasn't changed from MODIFIED to ON_QA due to the following reason:

[TAG 'ovirt-engine-3.6.11' DOESN'T CONTAIN PATCH 'https://gerrit.ovirt.org/74826']
gitweb: https://gerrit.ovirt.org/gitweb?p=ovirt-engine.git;a=shortlog;h=refs/tags/ovirt-engine-3.6.11

For more info please contact: rhv-devops

Comment 8 Artyom 2017-04-09 13:29:54 UTC

Checked on rhevm-3.6.11-0.2.el6.noarch

Bug still exists

POST request:
<cluster>
  <name>test</name>
  <data_center id="00000001-0001-0001-0001-000000000298" />
  <cpu id="Intel Conroe Family"/>
</cluster>

POST response:
<fault>
<reason>Operation Failed</reason>
<detail>[KSM or balooning must be enabled to allow memory optimization.]</detail>
</fault>

Comment 9 Martin Sivák 2017-04-12 14:22:44 UTC

The 3.6 engine build was accidentally done from an old tag. There will be a new one tomorrow...

Comment 11 Artyom 2017-04-16 07:56:15 UTC

Verified on rhevm-3.6.11.1-0.1.el6.noarch

Comment 13 errata-xmlrpc 2017-05-09 17:04:14 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.

https://access.redhat.com/errata/RHEA-2017:1210