

All about Two-Phase Locking and a little bit MVCC - javinpaul
http://www.cubrid.org/blog/cubrid-life/all-about-two-phase-locking-and-a-little-bit-mvcc/

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shin_lao
This is an extremely confusing explanation of MVCC an 2PL.

MVCC is about keeping all the versions of an entry and associating an unique
timestamp with each entry. Its advantages are scalability, no deadlock and
simplicity. Its drawbacks are increased memory consumption, the requirement
that all nodes must be synchronized and that all elementary operations must be
atomic.

2PL is a straightforward albeit pessimistic approach. Lock access to your
data, make your modification, and then release. Its advantages are reliability
and tight memory consumption. Its drawbacks are the lack of scalability and
potential deadlocks.

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jstclair
Slight correction: Microsoft SQL Server added MVCC in 2005
(READ_COMMITTED_SNAPSHOT).

