Bug 1282076

Summary:	cache mode must be the default mode for tiered volumes
Product:	[Community] GlusterFS	Reporter:	Dan Lambright <dlambrig>
Component:	tiering	Assignee:	Dan Lambright <dlambrig>
Status:	CLOSED CURRENTRELEASE	QA Contact:	bugs <bugs>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	mainline	CC:	bugs
Target Milestone:	---
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	glusterfs-3.8rc2	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:
Clones:	1283288 1283410 (view as bug list)		Environment:
Last Closed:	2016-06-16 13:44:23 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	1283288, 1283410

Description Dan Lambright 2015-11-14 19:27:55 UTC

Description of problem:

Make cache mode the default for tiering

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


How reproducible:

always

Steps to Reproduce:
1. 
2. 
3.

Actual results:

test mode is default

Expected results:

cache mode is default

Additional info:

test mode is for internal QE testing and should not be used by customers. Test mode forces all unused data to be destaged from the hot tier when no IO is received, rendering the SSD unused / wasted. If the demote cycle time is made large as a workaround, data will stay on the hot tier but will not react to changing conditions, which means unused data may fill the hot tier resource. A long cycle times also means the system will stay static even when close to full, which will put the system into a degraded mode. 

The cache mode is supposed to keep data on the hot tier but also demote data quickly when the hot tier is close to full. The cycle time can be set to a desired reaction time to swap out lesser used data and bring in more frequently accessed data without flushing the entire SSD.

Comment 1 Vijay Bellur 2015-11-14 19:57:34 UTC

REVIEW: http://review.gluster.org/12581 (cluster/tier make cache mode default for tiered volumes) posted (#1) for review on master by Dan Lambright (dlambrig)

Comment 2 Vijay Bellur 2015-11-17 12:18:33 UTC

COMMIT: http://review.gluster.org/12581 committed in master by Dan Lambright (dlambrig) 
------
commit dcd1ff344d242f64f3a5c579df97a050736e6633
Author: Dan Lambright <dlambrig>
Date:   Sat Nov 14 14:35:26 2015 -0500

    cluster/tier make cache mode default for tiered volumes
    
    The default mode for tiered volumes must be cache. The current
    test mode was for engineering and should ordinarily not be used
    by customers.
    
    Change-Id: I20583f54a9269ce75daade645be18ab8575b0b9b
    BUG: 1282076
    Signed-off-by: Dan Lambright <dlambrig>
    Reviewed-on: http://review.gluster.org/12581
    Tested-by: Gluster Build System <jenkins.com>
    Reviewed-by: mohammed rafi  kc <rkavunga>

Comment 3 Mike McCune 2016-03-28 22:28:36 UTC

This bug was accidentally moved from POST to MODIFIED via an error in automation, please see mmccune with any questions

Comment 4 Niels de Vos 2016-06-16 13:44:23 UTC

This bug is getting closed because a release has been made available that should address the reported issue. In case the problem is still not fixed with glusterfs-3.8.0, please open a new bug report.

glusterfs-3.8.0 has been announced on the Gluster mailinglists [1], packages for several distributions should become available in the near future. Keep an eye on the Gluster Users mailinglist [2] and the update infrastructure for your distribution.

[1] http://blog.gluster.org/2016/06/glusterfs-3-8-released/
[2] http://thread.gmane.org/gmane.comp.file-systems.gluster.user