On Thu, Jul 28, 2016 at 8:39 PM, Tatsuo Ishii <ishii@postgresql.org> wrote:
> BTW, is there any opposite information, i.e. showing the
> limitation of MySQL comparing with PostgreSQL?
I'm not aware of a general list on the topic, but in reviewing
academic papers regarding transaction isolation I did find (and
confirm) that MySQL InnoDB relaxes the "strict" aspect of the
Strict 2 Phase Locking they use for implementing serializable
transactions. "For performance reasons" they drop the locks
acquired during the transaction *before* ensuring crash/recovery
persistence. This is more-or-less equivalent to always running
with synchronous_commit = off as well as allowing a small window
for serialization anomalies in corner cases. The PostgreSQL
synchronous_commit option allows a similar performance benefit
(where the trade-off is deemed justified) without risking data
integrity in the same way.
--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company