On Mon, Jan 30, 2012 at 3:37 PM, Nicolas Spiegelberg <[email protected]> wrote: > However, I think > it's safe to say that there are multiple instances where the DBA team and > the AppServer team are different people, especially with any group > exploring multi-tenancy. For that use case, client & server compat is > critical. >
Sounds like we have a new requirement for the rpc compatibility work, that rpc/zk must continue to work w/ clients as old as 0.89fb. I could see how we might make it work for rpc switching on volunteered header or running with multiple engines, one for old stuff and another for the new, as Andrew suggests. I'm not sure how it'd work for zk serialized data given it started to be versioned in 0.92 only (0.89fb writes using RecoverableZK, 0.90 does not... so maybe we can skip 0.90?). Trying to narrow the need to the client-server only communication buys us near nought; the only interface particular to intra-servers communication is the http://hbase.apache.org/xref/org/apache/hadoop/hbase/ipc/HMasterRegionInterface.html. Its the other two, the admin interface http://hbase.apache.org/xref/org/apache/hadoop/hbase/ipc/HMasterInterface.html, and the client interface, http://hbase.apache.org/xref/org/apache/hadoop/hbase/ipc/HRegionInterface.html, that are fat. St.Ack
