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Static Variables: Grave Danger

I lost the whole last week on a very small issue. Issue of a kind that would be considered very silly if looked at later. Static variables for holding a Transactional object. This is probably a very naaive concept in Java (or any other language with statics). But mistakes are mistakes. We learn from them everyday. This time, I leart from some one else's. Not the static concept itself, but the sleepless nights it may drive you into for no reason.

The issue started last monday. We were seeing transactional attributes of an object replicated in other objects in the database. An application that stood well in multiple regression tests, load tests, stress tests, failed dramatically in production. To add to confusion, this was happenning exactly at a time where we had a batch job running, a lot of users logging in (of the order 50 logins/ sec), and most of these first time users.

To narrow down our variables, we stopped the batch job. that was in our control. Still There logins, a lot of them. We dint know what the users action was and what was causing it..

(To be continued..)

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