[omniORB] Connect failures in omniORB 4.1.1 stress test

[Peter Klotz]

In a simple stress test setup where a constant number of clients 
continuously contacts omniNames I keep obtaining sporadic 
CORBA::TRANSIENT (TRANSIENT_ConnectFailed) exceptions.

The exceptions only occur when raising the number of client applications 
into the region of 200. It does not matter if all clients run on the 
same machine or are distributed among several hosts.

omniNames always runs separated from the clients on its own machine. All 
processes run under Linux.

All clients are linked against omniORB 4.0.6 to allow for comparison.

I tried it with omniNames 4.1.0, 4.1.1 and 4.1.1 (CVS 2008-02-04). In 
all these cases the clients show sporadic connection problems.

When I use omniNames 4.0.7 (CVS 2008-02-04) no such behavior occurs. 
Even 200 clients can connect without problems.

I start omniNames without any special options, just "-ORBendPoint 
giop:tcp:<host>:<port>" is used.

The clients are started using option "-ORBInitRef 
NameService=corbaname::<host>:<port>".

Since the clients are always the same I would assume a server side 
problem in omniNames. However omniNames does not log anything unusual 
nor does it become instable.

I would rule out machine limits since 100 clients from a single machine 
work fine whereas 200 clients uniformly distributed among 4 machines 
lead to client side connection problems.

Find attached the source of the client program together with two 
scripts. StartClient.sh keeps running a single client in an infinite 
loop, StartClients.sh starts the other script for a given number of times.

Any ideas regarding this odd behavior are welcome.

Best regards, Peter.
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