Re: RMI round trip to create the object

Robert Klemme <>
Mon, 23 Apr 2007 11:03:48 +0200
On 23.04.2007 10:58, wrote:

I am writing a Java client server application in which the clients
resides in a long physical distance from the server. For example,
clients can be in India while server is San Jose. There is a secured
TCP connection between the clients and the server and the connection
between clients and server is done using RMI.
The thing is I noticed a performance drop due to the fact that RMI is
doing two round trips in order to execute single method: one round
trip is to create the object (Naming.lookup) and then another one is
to invoke the method on the object. Each round trip takes an overhead
of 1-2 seconds just to get from the client to the server. Logically, I
don't have any sequential calls on the same object so its actually a
performance cost I pay for each method invocation (every time user is
opening a window or something like that).

Is there any way I can combine the two round trips into one in order
to save one round trip cost?

Probably not - other than caching object references around in the client
so the lookup is a local lookup.

On a more general scale I'd say your design is probably not optimal: RMI
(as CORBA and like protocols) give you remote access to individual
methods. Having said that, they work best with fast network
connections. In your case you probably need to redesign to a) either
choose another protocol or b) provide objects as interface that have
less overhead, i.e. methods that do more in one invocation.

Kind regards


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