* should use Lock when mutating the flag
* same problem in MVHashMap.Write
* hole the rlock while reading WriteCell
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Co-authored-by: zhiqiangxu <652732310@qq.com>
A reverted transaction, X, can incorrectly write to a slot, which might be read by another transaction, Y. If we skip checking states written by X, then Y might end up with reading the wrong value and we won't be able to detect this error.
Added tests for executor and some improvements:
1. Add a dependency map during execution. This will prevent aborted tasks from being sent for execution immedaitely after failure.
2. Change the key of MVHashMap from string to a byte array. This will reduce time to convert byte slices to strings.
3. Use sync.Map to reduce the time spent in global mutex.
4. Skip applying intermediate states.
5. Estimate dependency when an execution fails without dependency information.
6. Divide execution task queue into two separate queues. One for relatively certain transactions, and the other for speculative future transactions.
7. Setting dependencies of Txs coming from the same sender before starting parallel execution.
8. Process results in their semantic order (transaction index) instead of the order when they arrive. Replace result channel with a priority queue.
