Connection.Open hanging/freezing
Posted: Fri 06 Dec 2013 10:04
Hi everyone,
I'm sorry I have to start such a squishy post, but we're pretty much out of ideas...
About half a year ago we started noticing problems with OracleConnection.Open if network issues came up. Every now and then (once every two to three weeks) an OracleConnection.Open would freeze the thread and not return. Never... And we were not able to find any clue, schema or hint on what could've caused it and how we could reproduce it.
To be at least able to detect the problem and not freeze up any working Process, we started calling it from within a new Task so we're able to cancel it after x seconds, throw an Exception and continue working. Although we had to take the performance hit it was important to us to at least know that there's a problem.
A couple of weeks ago we started testing our applications over crappy network connections by using SoftPedia Connection Emulator. Although we still can't give any details on what triggers the freezing, we're now at least able to reproduce it each day in at least one testcase. At one point, any subsequent calls to connection.Open on Connections having the same connectionString as the connection that froze first would hang;
Long story short:
* Random freezing on connection.Open with Devart 7.2.114 (Which is used by our 2.5 release)
* sometimes any following connection openings with the same ConnectionString will fail as well.
* Problems seems much less frequent in Devart 7.9.333 (which is used by our 2.6 release)
Any now my questions:
* Do you know what could trigger this behavior?
* Did you have this problem yourself too once in a while?
* Do you know if any changes were made between 7.2.114 and 7.9.333 that would explain the improvement?
Upgrading the Devart Version from 7.2 to 7.9 in our 2.5 release would take several days, not to think of addins developed by other departments that would require retesting, so I'd like to be rather sure it'd improve the situation before walking down that path...
BR && thanks a lot for any help,
Klaus
I'm sorry I have to start such a squishy post, but we're pretty much out of ideas...
About half a year ago we started noticing problems with OracleConnection.Open if network issues came up. Every now and then (once every two to three weeks) an OracleConnection.Open would freeze the thread and not return. Never... And we were not able to find any clue, schema or hint on what could've caused it and how we could reproduce it.
To be at least able to detect the problem and not freeze up any working Process, we started calling it from within a new Task so we're able to cancel it after x seconds, throw an Exception and continue working. Although we had to take the performance hit it was important to us to at least know that there's a problem.
A couple of weeks ago we started testing our applications over crappy network connections by using SoftPedia Connection Emulator. Although we still can't give any details on what triggers the freezing, we're now at least able to reproduce it each day in at least one testcase. At one point, any subsequent calls to connection.Open on Connections having the same connectionString as the connection that froze first would hang;
Long story short:
* Random freezing on connection.Open with Devart 7.2.114 (Which is used by our 2.5 release)
* sometimes any following connection openings with the same ConnectionString will fail as well.
* Problems seems much less frequent in Devart 7.9.333 (which is used by our 2.6 release)
Any now my questions:
* Do you know what could trigger this behavior?
* Did you have this problem yourself too once in a while?
* Do you know if any changes were made between 7.2.114 and 7.9.333 that would explain the improvement?
Upgrading the Devart Version from 7.2 to 7.9 in our 2.5 release would take several days, not to think of addins developed by other departments that would require retesting, so I'd like to be rather sure it'd improve the situation before walking down that path...
BR && thanks a lot for any help,
Klaus