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Locks on buffer blocks are unrelated to locks used for concurrency-control of transactions, and releasing them in a non-two-phase manner does not have any implications on transaction serializability. This is

Locks on buffer blocks are unrelated to locks used for concurrency-control of transactions, and releasing them in a non-two-phase manner does not have any implications on transaction serializability. This is Correct Answer Latches

These locks, and other similar locks that are held for a short duration.

Related Questions

Consider the following solution to the producer-consumer synchronization problem. The shared buffer size is ?. Three semaphores empty, full and mutex are defined with respective initial values of 0, ? and 1. Semaphore empty denotes the number of available slots in the buffer, for the consumer to read from. Semaphore denotes the number of available slots in the buffer, for the producer to write to. The placeholder variables, denoted by P, Q, R, and S, in the code below can be assigned either empty or full. The valid semaphore operations are: wait ( ) and signal ( ). Producer: Consumer: do {         wait (P) ;         wait (mutex) ;         //Add item to buffer         signal (mutex) ;         signal (Q) ; } while (1) ; do {          wait (R) ;          wait (mutex) ;          //Consume item from buffer          signal (mutex) ;          signal (S) ; } while (1) ;   Which one of the following assignments to P, Q, R and S will yield the correct solution?
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