Bug 1329486

Document URL: 
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https://access.redhat.com/documentation/en-US/Red_Hat_Storage/3.1/html/Administration_Guide/Formatting_and_Mounting_Bricks.html#idp4069512

Section Number and Name:
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6.4.1. Creating Bricks Manually
 

Describe the issue: 
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There is a regression in the way zeroing the newly provisioned lvs works along with lvchange on a RHEL 6.8 setup.In order to disable zeroing,we either have to give the --zero n option during lvcreate itself or re-activate the LV.There's a 100% chance that the customer will hit a ~20% hit on any kind of writes that he does if the workaround steps aren't adhered to.

Quoting from the admin guide :

"lvchange --zero n VOLGROUP/thin_pool"

This works perfectly on a RHEL 6.7 testbed.

We need to add a note around this for RHEL 6.8 for the workaround for the regression.

 
Suggestions for improvement: 
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We need to get rid of "lvchange --zero n VOLGROUP/thin_pool" and add the --zero option to lvcreate itself :

lvcreate --thinpool vg1/thin_pool_1 --size 4T --chunksize 1280K --poolmetadatasize 16G --zero n

This should work and based on our testing,RHGS layered over RHEL 6.8 will be performant.


Additional information: 
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RHGS write regression bug : https://bugzilla.redhat.com/show_bug.cgi?id=1324236 ---> CLOSED

lvchange regression bug : https://bugzilla.redhat.com/show_bug.cgi?id=1328245