Skip to content

Multi-version concurrency control

Category: Distributed systems · Status: stub

One line: Keeping several versions of each record so that readers see a consistent snapshot while writers add new versions, instead of readers and writers locking each other out.

Also called: MVCC, snapshot isolation.

How it connects

flowchart LR
  n_mvcc["Multi-version concurrency control"]
  n_read_write_lock["Read-write lock"]
  n_mvcc ---|or| n_read_write_lock
  classDef center stroke-width:3px
  class n_mvcc center
  classDef outside stroke-dasharray: 4 3
  class n_read_write_lock outside

In each language
Elsewhere PostgreSQL ↗: each statement sees a snapshot, so reading never blocks writing; Clojure's STM ↗ also uses multiversion concurrency control

Where to read more