Possible memory leak because of Transaction.Restart

[bigwad]

Starcounter version: 3.0.

Issue type

• Bug
• Feature request
• Suggestion
• Question
• Cannot reproduce
• Urgent

Issue description

Transaction object releases unmanaged memory in Dispose or in finalizer if a client fails to call Dispose. When a client calls Dispose, the transaction object removes itself from .Net finalization queue for the sake of performance.
Later, if we call Transaction.Restart on the disposed transaction, it allocates a new transaction, but doesn't put itself back in the finalization queue, thus making it possible to leak a memory if a client doesn't call Dispose again.

Either restarting of a disposed transaction should be prohibited or the transaction should be kept in the finalization queue in such scenario.

Reproduction code snippet

[bigwad]

Worth mentioning. The issue is not something artificial - it's a kind of behavior Starcounter.Palindrom shows due to a yet unrevealed race condition. Using a disposed transaction object is ofc a bug on Starcounter.Palindrom side, but it shouldn't have such severe consequences as a memory leak.