Lazy and Speculative Execution

15 January 2007

Lampson: Lazy and Speculative Execution

Speculative: Optimistic Concurrency Control

nIn databases and transactional memory

nThe bet: Cconcurrent transactions don’t conflict

nThe idea:

oRun concurrent transactions without locks

oAtomically with commit, check for conflicts with committed transactions

▬In some versions, conflict with any transaction because writes go to a shared store

oIf conflict, abort and retry

nProblem: running out of resources