Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.

Bug 1588430

Summary:	[DOCS] BUFFER_QUEUE_LIMIT not honoured and causing "buffer queue is full" issue
Product:	OpenShift Container Platform	Reporter:	Nicolas Nosenzo <nnosenzo>
Component:	Documentation	Assignee:	Gaurav Nelson <gnelson>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Anping Li <anli>
Severity:	unspecified	Docs Contact:	Vikram Goyal <vigoyal>
Priority:	high
Version:	3.9.0	CC:	anli, aos-bugs, ewolinet, jokerman, mmccomas, nhosoi, nnosenzo, rmeggins, vhernand
Target Milestone:	---
Target Release:	3.9.z
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2018-07-16 01:39:19 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:

Comment 10 Noriko Hosoi 2018-06-15 17:05:03 UTC

This section:
https://docs.openshift.com/container-platform/3.9/admin_guide/overcommit.html#tune-buffer-chunk-limit

ends with this sentence which is not correct in some cases.

"The Fluentd buffer_queue_limit is 32."

The buffer_queue_limit is defined as follows in output-es-config.conf, output-es-ops-config.conf, output-es-retry.conf and output-es-ops-retry.conf:

buffer_queue_limit "#{ENV['BUFFER_QUEUE_LIMIT'] || '32' }"

The environment variable BUFFER_QUEUE_LIMIT is calculated as (FILE_BUFFER_LIMIT / (number_of_output * BUFFER_SIZE_LIMIT)).  In this formula, number_of_output would be 1 if all the logs are sent to 1 ElasticSearch only; incremented by 1 if ops ElasticSearch is additionally configured; incremented by 1 if the logs are also forwarded to other fluentd, so on.

So, if BUFFER_QUEUE_LIMIT has the default set of values (FILE_BUFFER_LIMIT = 256Mi, number_of_output = 1, BUFFER_SIZE_LIMIT = 8Mi), buffer_queue_limit would be 32.  If you want to change the buffer_queue_limit value, you need to change FILE_BUFFER_LIMIT.  (Theoretically, changing BUFFER_SIZE_LIMIT also affects buffer_queue_limit, but that's not what the users would like to do.)

Comment 11 Gaurav Nelson 2018-06-19 02:31:34 UTC

Thank you for the detailed description Noriko Hosoi.

I have created a PR to address this, PTAL https://github.com/openshift/openshift-docs/pull/10201

Preview: http://bug-1588430-fixes--gnelson-preview.netlify.com/openshift-enterprise/(head%20detached%20at%20fetch_head)/admin_guide/overcommit.html#tune-buffer-chunk-limit

Comment 12 Anping Li 2018-07-11 10:06:53 UTC

LGTM

Comment 13 Gaurav Nelson 2018-07-16 01:39:19 UTC

Updates are live at https://docs.openshift.com/container-platform/3.9/admin_guide/overcommit.html#tune-buffer-chunk-limit