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From Michael Stack <st...@duboce.net>
Subject Re: Getting started with HBase
Date Sat, 20 Oct 2007 00:20:44 GMT
Andrzej Bialecki wrote:
> That's excellent news - I just looked at the code, I think it would 
> require only minimal tweaks to use it together with other Hadoop 
> services running in "local" mode - e.g. it would be more convenient to 
> have the MiniHBaseCluster (or its modified version, let's call it 
> LocalHBaseCluster) handle the startup / shutdown itself, so that the 
> user applications could assume that all necessary services are already 
> running. I'm also going to check what is the startup time of 
> MiniHBaseCluster.
MiniHBaseCluster already has a shutdown method.  Construction of a 
MiniHBaseCluster starts up the cluster instance.  Would you like a 
different startup mechanism Andrzej?  If so, what would you suggest?

Otherwise, I"m thinking we'd move MiniHBaseCluster from src/test to 
src/java so it makes it into the hadoop-*-hbase.jar renaming it 
LocalHBaseCluster to follow the LocalJobRunner precedent.  We should 
also make the hbase.master value default "local" rather than 
"" and start a LocalHBaseCluster .  How does that sound?

See the content of src/test/hbase-default.xml if you want to tweak 
things to make startup faster.  The properties therein are the list to 
tune if you want to make startup and shutdown snappier. 

>> If the default mode -- i.e. if the hbase.master was set to 'local' in 
>> hbase-default.xml -- was to run a MiniHBaseCluster instance, would 
>> this suffice Andrzej?  Or do you need master and regionservers 
>> talking to each via direct in-process method invocations rather than 
>> over sockets as is done in "local" mapreduce?
> Direct in-process pseudo-protocol would be probably more efficient and 
> it would reduce the number of sockets in use, but we could implement 
> it as a future enhancement if needed. For now I'm happy with them 
> using sockets.

Agreed.  I do not think it would be hard having the master invoke region 
server methods directly (and vice versa) rather than go via the RPC but 
that we can be done later.


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