Add mutex around rng *rand.Rand to avoid data race on resume #156
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| @@ -1004,6 +1009,8 @@ func (r *Consumer) redistributeRDY() { | |||
| availableMaxInFlight = 1 - atomic.LoadInt64(&r.totalRdyCount) | |||
| } | |||
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| r.rngMtx.Lock() | |||
| defer r.rngMtx.Unlock() | |||
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can we reduce the size of this critical path and put this lock around just the call to r.rng.Int()?
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thanks for this, just one minor comment! |
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I've addressed the comment. |
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LGTM, do you mind squashing down to one commit? |
| @@ -106,7 +106,8 @@ type Consumer struct { | |||
| channel string | |||
| config Config | |||
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| rng *rand.Rand | |||
| rngMtx sync.RWMutex | |||
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RWMutex is designed for separate read and write locks. Since we only want global locking can you use sync.Mutex here?
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Squashed and changed to using sync.Mutex. |
mreiferson
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Sep 2, 2015
Add mutex around rng *rand.Rand to avoid data race on resume
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Currently there is a data race when a consumer hits a backoff condition and then resumes. The resume via time.AfterFunc gets called from a different goroutine.
Note: this could also have been solved using one of the existing mutexes (r.mtx or r.backoffMtx).