We are looking to use buckets as our "primary key" (e.g. to keep all documents for a given account together, in one shard).
As a single shard will probably have a million or more documents, spanning 50-500 accounts, we are concerned with optimizing queries (e.g. minimizing the IO required to serve a query).
Where can we find information about how buckets are stored within the shard?
Thank you!