Fix races in CQ execution #2553
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These races were flagged here: |
| @@ -3955,6 +3953,18 @@ func (s *Server) runContinuousQuery(cq *ContinuousQuery) { | |||
| cq.mu.Lock() | |||
| defer cq.mu.Unlock() | |||
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| // Get server CQ parameters under lock, to avoid races. | |||
| s.mu.RLock() | |||
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do we really need to lock on these? They can't ever get updated on a running process. They're set when the server object is created and never set again.
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Perhaps not. This may be rather pedantic. This was a drive-by change -- the real race is around lastRun which was being written and read from different goroutines.
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I can pull this change. I agree that these settings never change.
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yeah, this seems sane to me, even if it only could ever fail during testing. +1 |
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This change refactors the CQ code such that "should run" is checked within the goroutine that the CQ will run, if it does run. This avoids the race, at the cost a very-short lived goroutine if the CQ is not run.