Zones

[kocolosk]

No description provided.

[kocolosk]

You should pass the #full_doc_info to couch_db:open_doc/2 here to avoid unnecessary btree ops.

Also, just a stylistic point, but what about including the Db in the accumulator instead of inlining the fold function?

[rnewson]

I'll do both, though I note that inlining it was a style choice on my part.

[kocolosk]

The indentation convention in mem3 is 4 spaces, we'll need to convert the tabs used throughout this patch.

[kocolosk]

We'll also want to add a clause to the code_change function in mem3 to convert the existing list to a dictionary

[kocolosk]

The patch makes the top-level properties of each document in the nodes DB available via mem3:node_info/2, but only the _ec2 variant uses this information when choosing shards for a DB. I'd prefer it if we have an algorithm that uses the "zone" field in the document in the same manner as mem3_choose_ec2 when placing shards but does not try to query the EC2 metadata API to set the content of that field.

[kocolosk]

Closed by merging the backport_zones branch

94e2d5