XFS on top of LVM span in AWS. Stripe or are AG's good enough?

[Jeff Gibson]

So I'm creating an LVM volume with 8 AWS EBS disks that are spanned (linear) per Redhat's documentation for Gluster (https://access.redhat.com/documentation/en-US/Red_Hat_Storage/3.1/html/Deployment_Guide_for_Public_Cloud/ch02s03.html#Provisioning_Storage_for_Three-way_Replication_Volumes).

2 questions-

1.  Will XFS's Allocation Groups essentially stripe the data for me or should I stripe the underlying volumes with LVM?  I'm not worried as much about data integrity with a stripe/span since Gluster is doing the redundancy work.

2.  AWS volumes sometimes have inconsistent performance.  If I understand things correctly, AG's run in parallel.  In a non-striped volume, if some of the AGs are temporarily slower to respond than others due to one of the underlying volumes being slow, will XFS prefer the quicker responding AGs or is I/O always evenly distributed?  If XFS prefers the more responsive AG's it seems to me that it would be better NOT to stripe the underlying disk since all AG's that are distributed in a stripe will continuously hit all component volumes, including the slow volume (unless if XFS compensates for this?)

Thank you
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