10.3.5. Implicit Pessimistic Locking Example

Procedure 10.4. Transaction with Implicit Pessimistic locking

1. When the line cache.put(K,V) executes, a cluster-wide lock is acquired on K.

   tx.begin()
   cache.put(K,V)
   

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2. When the line cache.put(K2,V2) executes, a cluster-wide lock is acquired on K2.

   tx.begin()
   cache.put(K,V)
   cache.put(K2,V2)
   

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3. When the line cache.put(K,V5) executes, the lock acquisition is non operational because a cluster-wide lock for K has been previously acquired. The put operation will still occur.

   tx.begin()
   cache.put(K,V)
   cache.put(K2,V2)
   cache.put(K,V5)
   

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4. When the line tx.commit() executes, all locks held for this transaction are released.

   tx.begin()
   cache.put(K,V)
   cache.put(K2,V2)
   cache.put(K,V5)
   tx.commit()
   

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