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The Selenium Grid Hub distribute the tests launched between the registered RCs, but if there is no available RCs, it will enqueue them.

Anyone knows the max size of this queue?

I'm asking this because i suspect that if you enqueue a big number of tests and you have the RCs running remotely, the Hub is not fully able to manage the requests and the RC session is not properly released when the test finish, therefore when you run the next test it will fails because it will use that RC not properly released.

In my case, i'm having this problem with this configuration:

-Debian server with Selenium Grid 1.0.8 running the Hub.

-A Windows virtual machine with Selenium Grid 1.0.8 and IE running the RC and registering it against the Debian Hub.

If i run from the Debian machine the tests one by one, the tests pass, but if i run a lot of tests concurrently the first test pass but the next ones fails.

Any idea of what is happening?

Thanks in advance


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2 Answers 2

up vote 2 down vote accepted

After a first look at RegistrationServlet.java and Registry.java in the Selenium source code, it looks like new requests just wait for available slots with a locking mechanism.

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There is no size limit, other than what your VM can handle. There is a configuration setting to timeout clients if they're unable to get a session within a given time interval.

Please see the newSessionMaxWaitTimeInSeconds value in the Selenium Grid docs.

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