Bug 1841959

Summary:	pstack review for IPA ns-slapd temporary hang, may be related to bz 1724761 Entry cache contention
Product:	Red Hat Enterprise Linux 8	Reporter:	Marc Sauton <msauton>
Component:	slapi-nis	Assignee:	Alexander Bokovoy <abokovoy>
Status:	NEW ---	QA Contact:	ipa-qe <ipa-qe>
Severity:	high	Docs Contact:
Priority:	unspecified
Version:	---	CC:	cobrown, ddas, nsuryawa, pasik, sandro.valentini, spichugi, tbordaz, vashirov
Target Milestone:	rc	Keywords:	Triaged
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:		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 11 Deepak Das 2020-07-01 12:13:01 UTC

Hi,

Latest update from customer.

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>> This is something we expect RH to let us know.  Is it related to deref ? What is the risk and impact of this change ?
<<As this is a Bug, we will not be able to predict the behavior or what is causing it, which is why we involved our Developers. there is low to no risk of disabling deref.
Ok, could you please point me to the RH documentation so we evaluate this suggestion ?

  - When the hang occurs, how long does it last. Could you collect 'top -H' at that time and get more frequent pstack
>>There are several thread dumps attached to this case which are taken automatically and programmatically.
<<We have reviewed the pstacks provided. The developers assisting on this case would like a pstack or series of 3 or 4 that happen at the time specified.
Ok, I am adapting the temporary monitoring scripts and will soon provide new dumps.

>>In regards to top -h, please let us know how to perform this programmatically.
<<We do not provide scripts so, at best we could give you the command to run.
Ok, it can be done with ( top -H -n 1 > top_output_$$.txt ). I will upload together with the above dumps.

<<Could you confirm if the following attribute is set to 'nsslapd-db-deadlock-policy=6' ?
Yes, it is still set to 6 since update on (Tue, Jun 16, 2020, 4:00:03 PM GMT+2).
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Comment 15 Petr Čech 2021-02-19 12:32:00 UTC

Thank you taking your time and submitting this request for Red Hat Enterprise Linux 7.
Red Hat Enterprise Linux 7 is in Maintenance Support 2 Phase. This bug was reevaluated and will be postponed to RHEL 8.
Thank you for understanding.
Red Hat Enterprise Linux Identity Management Team