Regarding this: On Mon, Sep 10, 2012 at 12:13 PM, Matt Corgan <mcor...@hotpads.com> wrote: > 1) Per-region or Per-table [...] > 1) > - Per-region: the index entries are stored on the same machine as the > primary rows > - Per-table: each index is stored in a separate table, requiring > cross-server consistency
LarsH and I were discussing this a bit. This doesn't have to be a choice, it could be possible to have both, a separate table for index storage, and colocation of the index table regions and primary table regions on the same regionserver so cross-region consistency issues can be dealt with through low latency in-memory channels. (With fallback to cross-server consistency mechanism when placement can't be ideal when the cluster is out of steady state due to failure/churn.) The master might assign primary and index regions out together as a group. Best regards, - Andy Problems worthy of attack prove their worth by hitting back. - Piet Hein (via Tom White)
