Forum Bugs

Prince instances get stuck in memory


We're in the process of reorganizing/moving functionality and one of those things is moving which applications we do our Prince processing in. We've found as we move traffic onto the new apps and servers, our load tends to cause instances of Prince to get stuck in memory and not complete. Eventually this becomes a resource drain that makes the server unusable unless someone goes onto the server to kill the lingering Prince instances.

We're having difficulty nailing down a solution. Logs seem to indicate it gets hung up on retrieving images and then abandons the job. Our setup allows us to use the new and old process in parallel so we can see the same load is handled on existing servers without an issue. The executable is accessed in the same way in both applications, using the C# commands for Process.Start(...) and the same configuration/sources.

We are currently using 11.4 and are in the process of upgrading to 14.2 but through experimentation we've validated the problem continues with both versions.

We're really at a loss as to what to try next. Any suggestions or help would be greatly appreciated.

If you are not using our C# wrapper, can you confirm that you are handling Prince log output correctly? It is possible for Prince to deadlock if it attempts to write log messages to stderr and nothing is reading them.
We have a toggle in place to add an attribute to the command line for the error logging to output to a file. We're seeing the issue both when the logging attribute is present and absent.
The thread has gone silent here. For our part we're testing out using the C# wrapper instead and we've seen good results in our test environment.
Please let us know if you see the issue again with the C# wrapper.
Looks like the issue has been resolved by moving to the wrapper. Thanks!