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Bug 1801965

Summary: [RHEL8][I/O Performance Tuning] how to change "readahead" value for a device in persistent way?
Product: Red Hat Enterprise Linux 8 Reporter: xhe <xhe>
Component: util-linuxAssignee: Karel Zak <kzak>
Status: CLOSED NOTABUG QA Contact: Radka Brychtova <rskvaril>
Severity: high Docs Contact:
Priority: unspecified    
Version: 8.1   
Target Milestone: rc   
Target Release: 8.0   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: If docs needed, set a value
Doc Text:
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Clone Of: Environment:
Last Closed: 2020-06-11 10:36:22 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 2 Karel Zak 2020-02-17 13:47:46 UTC
Yes, the ioctl BLKRASET (used by blockdev) is based on 512-byte sectors.

Anyway, I don't know about any elegant way how to set up it in a persistent way. 

Something is in 
   https://access.redhat.com/solutions/4378581
   https://access.redhat.com/solutions/1241093

Maybe extra udev rule is also not bad idea.