REVIEW: http://review.gluster.org/13601 (cluster/tier: WIP optimize lookups for tiering) posted (#1) for review on master by Dan Lambright (dlambrig)

REVIEW: http://review.gluster.org/13601 (cluster/tier: WIP optimize lookups for tiering) posted (#2) for review on master by Dan Lambright (dlambrig)

REVIEW: http://review.gluster.org/13601 (cluster/tier: optimize lookups for tiering) posted (#3) for review on master by Dan Lambright (dlambrig)

REVIEW: http://review.gluster.org/13601 (cluster/tier: WIP optimize lookups for tiering) posted (#4) for review on master by Dan Lambright (dlambrig)

I think the dependency between upstream and downstream bug is reversed here:

- This (bug #1314586) is the upstream bug.
- Bug #1292391 is the downstream bug.

we have:

- upstream bug depends on downstream bug.

which makes no sense, imho, since we first
need to fix the bug upstream before we can
port the fix to downstream. Hence we should have:

- downstream bug depends on upstream bug.

my 2 cents.

Patch https://review.gluster.org/#/c/glusterfs/+/21331/ removes tier functionality from GlusterFS. 

https://bugzilla.redhat.com/show_bug.cgi?id=1642807 is used as the tracking bug for this. Recommendation is to convert your tier volume to regular volume (either replicate, ec, or plain distribute) with "tier detach" command before upgrade, and use backend features like dm-cache etc to utilize the caching from backend to provide better performance and functionality.