On the Scalability of Snapshot Isolation

A paper item under the directory: distributed transactions

Two properties help with //scalability// of a transactional system: genuine partial replication (GPR), which leverages the intrinsic parallelism of a workload, and snapshot isolation (SI), which decreases the need for synchronization. However, it is ''impossible'' to have both SI and GPR.

SI is decomposed into four properties:

• every transaction sees a committed state (ACA),
• every transaction observes a strictly consistent snapshot (SCONS),
• snapshots are monotonic (MON),
• write-conflict free (WCF)

$SI = ACA \cap SCONS \cap MON \cap WCF$