Hi
I'm porting the region level HBase SE to the new SE iface and I have a
couple of questions.
1- about the method: public ListMultimap<ReadEntry, DrillbitEndpoint>
getReadLocations(Collection<ReadEntry> entries)
when does it happen that a read entry gets assigned more that one
drillbits?
in terms of hbase I can see the case where multiple read entries get
assigned to the same drillbit (co-located regions) but I can't envision a case
where the same read entry (usually corresponding to a shard or partition) gets
assigned to multiple drillbits. when can that happen?
2- with regard to off-heap storage and underlying SE co-location
this is not really a doubt, just checking that my reasoning is correct
before.
for co-located underlying SE and Drillbit's we should use off-heap,
shared memory for IPC when possible, correct?
Specifically I'm investigating the possibility of having HBase store
region scan data directly off heap and making the results from hbase contain a
set references to aligned shared memory locations.
I'm not sure I'll be implementing this immediately but I'd like to
design accounting for it if that is the idea.
Also this means that SE's must work in two modes: co-located with
shared memory and remote with sockets. We'd then have the
Jacques: I'm sure you've put some thought to the underlying mechanics
on how to accomplish this, could you share some quick ideas/references?
Best
David
