ChallengeThe invisible concurrency bug
A customer reported an error when a certain query was run concurrently. It took a while, but we finally found the piece of code that is responsible for this:
Can you spot it?
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Comments
I'm not an expert on exactly delegates unwind in compiled version, but you are not using
Engine e
in the delegate, butengine
from outside scope directly. Which I guess is not intentional since you are passing it in the last line.Question: whole method is basically a delegate definition and then calling it - why not execute the code directly without a delegate?
Use ConcurrentDictionary ?
[valueType] = convert gets run after the interlocked?
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