hbase-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From N Keywal <nkey...@gmail.com>
Subject Re: understanding the client code
Date Tue, 29 May 2012 15:25:16 GMT
So it's the right place for the internals :-).
The main use case for the thrift api is when you have non java client code.

On Tue, May 29, 2012 at 5:07 PM, S Ahmed <sahmed1020@gmail.com> wrote:
> I don't really want any, I just want to learn the internals :)
>
> So why would someone not want to use the client, for data intensive tasks
> like mapreduce etc. where they want direct access to the files?
>
> On Tue, May 29, 2012 at 11:00 AM, N Keywal <nkeywal@gmail.com> wrote:
>
>> There are two levels:
>> - communication between hbase client and hbase cluster: this is the
>> code you have in hbase client package. As a end user you don't really
>> care, but you care if you want to learn hbase internals.
>> - communication between customer code and hbase as a whole if you
>> don't want to use the hbase client. Then several options are
>> available, thrift being one of them (I'm not sure of avro status).
>>
>> What do you want to do exactly?
>>
>> On Tue, May 29, 2012 at 4:33 PM, S Ahmed <sahmed1020@gmail.com> wrote:
>> > So how does thrift and avro fit into the picture?  (I believe I saw
>> > references to that somewhere, are those alternate connection libs?)
>> >
>> > I know protobuf is just generating types for various languages...
>> >
>> > On Tue, May 29, 2012 at 10:26 AM, N Keywal <nkeywal@gmail.com> wrote:
>> >
>> >> Hi,
>> >>
>> >> If you're speaking about preparing the query it's in HTable and
>> >> HConnectionManager.
>> >> If you're on the pure network level, then, on trunk, it's now done
>> >> with a third party called protobuf.
>> >>
>> >> See the code from HConnectionManager#createCallable to see how it's
>> used.
>> >>
>> >> Cheers,
>> >>
>> >> N.
>> >>
>> >> On Tue, May 29, 2012 at 4:15 PM, S Ahmed <sahmed1020@gmail.com> wrote:
>> >> > I'm looking at the client code here:
>> >> >
>> >>
>> https://github.com/apache/hbase/tree/trunk/hbase-server/src/main/java/org/apache/hadoop/hbase/client
>> >> >
>> >> > Is this the high level operations, and the actual sending of this data
>> >> over
>> >> > the network is done somewhere else?
>> >> >
>> >> > For example, during a PUT, you may want it to write to n nodes, where
>> is
>> >> > the code that does that? And the actual network connection etc?
>> >>
>>

Mime
View raw message