Bug 2227309

Summary:	[RFE] mds: add balance_automate fs setting
Product:	[Red Hat Storage] Red Hat Ceph Storage	Reporter:	Manny <mcaldeir>
Component:	CephFS	Assignee:	Patrick Donnelly <pdonnell>
Status:	CLOSED ERRATA	QA Contact:	Hemanth Kumar <hyelloji>
Severity:	high	Docs Contact:	Akash Raj <akraj>
Priority:	high
Version:	5.3	CC:	akraj, ceph-eng-bugs, cephqe-warriors, gfarnum, hyelloji, mcaldeir, ngangadh, pdonnell, tserlin, vshankar
Target Milestone:	---	Keywords:	FutureFeature
Target Release:	7.1
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	ceph-18.2.1-26.el9cp	Doc Type:	Enhancement
Doc Text:	.MDS dynamic metadata balancer is off by default. Previously, poor balancer behavior would fragment trees in undesirable ways by increasing the `max_mds` file system setting. With this enhancement, MDS dynamic metadata balancer is off, by default. Operators must turn on the balancer explicitly to use it.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2024-06-13 14:20:43 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:	2255435, 2255436, 2267614, 2298578, 2298579

Description Manny 2023-07-28 16:42:52 UTC

Description of problem:  RFE: change default value of "mds_bal_interval" to "0", aka false

From case 03492882 and BZ (https://bugzilla.redhat.com/show_bug.cgi?id=2203258) we see that having "mds_bal_interval" enabled results in performance issue. Beyond the log evidence in BZ 2203258, the customer reports that Ceph FS latency has dropped by 75 percent and I/O in the cluster has doubled since "mds_bal_interval" was set to false on their system.

We'd like to see the change in 5.3z-whatever and 6.1z-whatever and beyond

See also KCS #7026124, (https://access.redhat.com/solutions/7026124)

This same customer commented if this feature hampers performance this much and there is no intention on fixing it, the default value should be changed.


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Comment 12 errata-xmlrpc 2024-06-13 14:20:43 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 (Critical: Red Hat Ceph Storage 7.1 security, enhancements, and bug fix update), 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/RHSA-2024:3925