On 2/4/11 10:58 PM, Stefan Seelmann wrote:
> Hi guys,
>
> one of our Hudson builds currently fails [1], the cause is an
> IOException (Too many open files). The reason this happens is that in
> our integration test (server-integ and ldap-api-test) we open real
> network connections. In many cases a new connection is opened in each
> test method. I also found a case where we open new connections within
> a loop.
I added some performance tests for each operation, but those tests are 
@Ignored.

What is the tests containing a loop ?
> Most times the connections is closed after usage. However, as you
> certainly know, there is still a problem with allocating many new
> connections: sockets remain in TIME_WAIT state for some time after
> bein closed, see [2]. On the Hudson servers we can of course increase
> the ulimit -n and reduce the TIME_WAIT value. But I think that won't
> scale when connections are opened in a loop.
Sure. We can also ask to have  short lived socket, like 5 secs. Usually, 
a socket remain in TIME_WAIT state for 30 secs on a standard linux box.
> I'd like to discuss possible options to improve the situation:
>
> - Fist I think in general we should avoid to create new connections
> within a loop in integration tests. We have other techniques to run
> such test [3]. In general such test patterns are stress or performance
> tests, but not integration tests.
+1
> - Second we should avoid to create a new connection for each test
> method. One option to achieve this is to use a single connection per
> test class without opening/closing them @Before/@After each test.
> Maybe the better option is to use a connection pool. Of course when
> testing connect/disconnect/bind/unbind it may be required to use a
> fresh connection objects.
If we use our client API, we have to add a pool into the API. In the 
tests where we use JNDI, we can use a pool, that's for sure.


-- 
Regards,
Cordialement,
Emmanuel Lécharny
www.iktek.com