Bug 1993296

Summary:	multipath performance regression with many devices
Product:	Red Hat Enterprise Linux 8	Reporter:	Pavel Cahyna <pcahyna>
Component:	rear	Assignee:	Pavel Cahyna <pcahyna>
Status:	CLOSED ERRATA	QA Contact:	David Jež <djez>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	8.5	CC:	djez, ovasik, pcahyna
Target Milestone:	beta	Keywords:	Regression, Triaged
Target Release:	8.5
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	rear-2.6-2.el8	Doc Type:	No Doc Update
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-11-09 18:53:41 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:	1973448

Description Pavel Cahyna 2021-08-12 17:48:31 UTC

Description of problem:
/CoreOS/rear/Regression/bz1672938-numerous-multipath-performance now fails.

When I extend the timeout, rear mkrescue in the test takes 4445s. In ReaR 2.4, it took 300s.

Version-Release number of selected component (if applicable):
2.6-1.el8

How reproducible:
easily, preferably on a machine with lots of RAM

Steps to Reproduce:
1. wow rhel-8.5 --reserve --arch x86_64  --taskparam=VERSIONLOCK=true --brew-build  rear-2.6-1.el8  --brew-method=multi /CoreOS/rear/Regression/bz1672938-numerous-multipath-performance

Actual results:
test fails

Expected results:
test should pass

Additional info:

this is due to this line https://github.com/rear/rear/pull/2299/files#diff-2916f533f1aa01a8a571a7062e43957bdd1523e70ce94a5107541ff466eef22cR705 
and the easiest fix is to comment it out, although it will reintroduce the problem that the line was supposed to fix - but we never had the fix anyway, so in RHEL it is not a regression.

Comment 10 errata-xmlrpc 2021-11-09 18:53:41 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 (rear bug fix and enhancement 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/RHEA-2021:4344