
Distributed Concurrency Control
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C1, C2, and C3 instead of maintaining one queue for each transaction manager at each site in the
distributed system. The timestamp scheduler will choose an operation of a transaction, with the
smallest timestamp value, for execution until there is at least one operation in each class C1, C2 or
C3 to which the transaction belongs.
8.6.3 Multi-version TO Algorithm
Multi-version TO algorithm is another timestamp-based protocol that reduces restart overhead of
transactions. In multi-version TO algorithm, the updates of data items do not modify the database,
but each write operation creates a new version of a ...