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• If the local txn is finished, return the response with the outcome: commit or abort. The txn state is stored in a local cache, mentioned in the RW section.
  
  If the local txn is finishing (waiting for finish state replication), wait for outcome and return response with the outcome: commit or abort
  
  If the outcome is to commit, additional timestamp check is required: a commit timestamp must be <= readTs. If the condition is not held, the outcome is changed to commit abort.
  
  If local txn is active, adjust the txn coordinator node HLC according to readTs to make sure the txn commit timestamp is above the read timestamp. The read timestamp must be installed before txn is started to commit, so commit timestamp is assigned after the read timestamp. This must be achieved by some sort of concurrency control, preferably non-blocking. In this case we must ignore the write intent, so the outcome is to abort.
  
  If txn state is not found in a local cache and txn is not active, return NULL.

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