Bug 1821584

Summary: [RHEL-8.2] Document the BIOS changes required for RHGS on RHEL8 platform
Product: [Red Hat Storage] Red Hat Gluster Storage Reporter: Nag Pavan Chilakam <nchilaka>
Component: DocumentationAssignee: Disha Walvekar <dwalveka>
Status: CLOSED WONTFIX QA Contact: Prasanth <pprakash>
Severity: high Docs Contact:
Priority: high    
Version: rhgs-3.5CC: bkunal, pprakash, puebele, rhs-bugs, sheggodu, storage-doc, storage-qa-internal
Target Milestone: ---Keywords: ZStream
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Last Closed: 2020-05-04 06:53:55 UTC Type: Bug
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Blocks: 1822630    

Description Nag Pavan Chilakam 2020-04-07 06:55:59 UTC 
Document URL: 
===============
We have seen issues wrt performance and timeouts due to the default BIOS settings in RHEL8
By default BIOS power manager mode is set to "Dynamic Power Savings Mode", under this category RHEL-7 is able to modify CPU scaling frequency to the maximum while RHEL 8 is using half of the maximum frequency. After changing the bios setting  to "OS Controlled" things are fixed.

If we don't change the above, below issues have been seen so far:
1) drop in performance
2) timeout issues as mentioned in BZ#1810516


hence this needs to go into all the respective RHGS guides
Comment 1 Patric Uebele 2020-04-07 08:41:28 UTC 
I'd suggest to add a section "BIOS Settings" in the prerequisites chapter 1.2: https://access.redhat.com/documentation/en-us/red_hat_gluster_storage/3.5/html/installation_guide/sect-prerequisites1

/Patric
Comment 2 Patric Uebele 2020-04-08 12:38:31 UTC 
(In reply to Patric Uebele from comment #1)
> I'd suggest to add a section "BIOS Settings" in the prerequisites chapter
> 1.2:
> https://access.redhat.com/documentation/en-us/red_hat_gluster_storage/3.5/
> html/installation_guide/sect-prerequisites1
> 
> /Patric

To add on my comment, make the statement in a generic way, as we probably can't cover every specific BIOS setting. And also add a similar note to the HW Compatibility KCS https://access.redhat.com/knowledge/articles/66206 

/Patric