Bug 1403814

Summary:	[Docs][Admin] Improve and complete memory based scheduling policy docs
Product:	Red Hat Enterprise Virtualization Manager	Reporter:	Doron Fediuck <dfediuck>
Component:	Documentation	Assignee:	Megan Lewis <melewis>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Tahlia Richardson <trichard>
Severity:	medium	Docs Contact:
Priority:	unspecified
Version:	4.0.5	CC:	gklein, lbopf, lsurette, mgoldboi, msivak, pdwyer, rbalakri, Rhev-m-bugs, srevivo, ykaul, ylavi
Target Milestone:	ovirt-3.6.11
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
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Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2017-04-13 01:37:10 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	Docs	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	1427748, 1440610

Description Doron Fediuck 2016-12-12 12:24:14 UTC

Description of problem:
Current documentation as can be seen in Table 4.5. Scheduling Policy Tab Properties available in [1] is inaccurate and incomplete.

Version-Release number of selected component (if applicable):
3.6 and later.

Actual results:
MaxFreeMemoryForOverUtilized and MinFreeMemoryForUnderUtilized definitions are inaccurate, as the migration happens while the host memory is below or above the requested service level.
Additionally we should provide sample values for users to try it out.

Additional info:

[1] https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Virtualization/3.6/html/Administration_Guide/sect-Cluster_Tasks.html

Comment 2 Martin Sivák 2016-12-12 12:32:25 UTC

I think there are two mistakes there:

> MaxFreeMemoryForOverUtilized: Sets the maximum free memory required in MB
> for the minimum service level

The maximum here means that the overutilized condition is over when you have more than the defined amount of free memory. So s/maximum/minimum would probably fix this.

> migrates virtual machines to other hosts in the cluster until the host's
> available memory is below the minimum service threshold

s/until/while as each VM that is migrated away increases the available memory of the source host

> MinFreeMemoryForUnderUtilized: Sets the minimum free memory required in MB
> before the host is considered underutilized. If the host's memory usage runs 
> below this value,

s/memory usage runs below/available memory runs above/

The original is technically correct, but mixing memory usage with available memory can confuse the reader.

Comment 3 Lucy Bopf 2017-01-11 04:31:44 UTC

Changing component to Documentation.

Comment 4 Lucy Bopf 2017-01-11 04:34:00 UTC

Assigning to Megan for review.

Comment 11 Megan Lewis 2017-04-13 01:37:10 UTC

The changes for this bug have now been published. 

4.0 
https://access.redhat.com/documentation/en-us/red_hat_virtualization/4.0/html-single/administration_guide/#Configuring_scheduling_policy

https://access.redhat.com/documentation/en-us/red_hat_virtualization/4.0/html-single/administration_guide/#Cluster_Scheduling_Policy_Settings

4.1 
https://access.redhat.com/documentation/en-us/red_hat_virtualization/4.1/html-single/administration_guide/#Configuring_scheduling_policy

https://access.redhat.com/documentation/en-us/red_hat_virtualization/4.1/html-single/administration_guide/#Cluster_Scheduling_Policy_Settings