[Cluster-devel] [PATCH 2/4] mkfs.gfs2: Align resource groups to RAID stripes

[Bob Peterson <rpeterso@redhat.com>]

| > In GFS1, we allowed mix-and-match resource group sizes, but we originally
| > Do we still want to enforce this rule?
| 
| Good question. I had assumed that we don't have a rule like that as the
| rindex specifies the rg sizes. My next planned mkfs change is to allow
| the journal creation code to ask for a resource group large enough to
| contain all of a journal's data blocks so that they're always a single
| extent. Returning to enforcing the rule would have implications for that
| plan, too.
| 
| Andy

Hi,

Some more thoughts to add to this discussion:

First, since we're now trying to align our rgrps to raid stripes, maybe
the rules no longer make sense.

Second, we probably want to change gfs2_grow to ensure that new rgrps
are also placed on the same stripe boundaries. If we enforce the uniform
rgrp rule, this would probably happen automatically. If we don't, I bet
gfs2_grow would need to change.

Bob Peterson
Red Hat File Systems