# Synchronous Replication

DevFeed: [Synchronous Replication](<https://devfeed.tech/articles/synchronous-replication-34392.md>)

Original publisher: [Read original article](<https://tapoueh.org/blog/2010/09/synchronous-replication/>)

Author: Dimitri Fontaine PostgreSQL Major Contributor; Author

Published: 2010-09-06T16:05:00Z

Content type: opinion

Language: en

Sources: [Dimitri Fontaine](<https://devfeed.tech/sources/dimitri-fontaine.md>)

Topics: [Replication](<https://devfeed.tech/topics/replication.md>), [Database](<https://devfeed.tech/topics/database.md>), [Transactions](<https://devfeed.tech/topics/transactions.md>)

Tags: [async](<https://devfeed.tech/tags/async.md>), [connectivity](<https://devfeed.tech/tags/connectivity.md>), [database](<https://devfeed.tech/tags/database.md>), [failover](<https://devfeed.tech/tags/failover.md>), [replication](<https://devfeed.tech/tags/replication.md>), [server](<https://devfeed.tech/tags/server.md>), [standby](<https://devfeed.tech/tags/standby.md>), [timeout](<https://devfeed.tech/tags/timeout.md>), [transactions](<https://devfeed.tech/tags/transactions.md>), [version](<https://devfeed.tech/tags/version.md>)

## AI overview

The article discusses a proposed synchronous replication facility for a database, including service levels based on whether data is received, flushed, or applied on a standby before COMMIT is acknowledged. It considers configuring failover servers and choosing safety requirements per transaction, including behavior when a standby loses connectivity.

## Source excerpt

Although the new asynchronous replication facility that ships with 9.0 ain't released to the wide public yet, our hackers hero are already working on the synchronous version of it. A part of the facility is rather easy to design, we want something comparable to DRBD flexibility, but specific to our database world. So synchronous would either mean recv, fsync or apply, depending on what you need the standby to have already done when the master acknowledges the COMMIT. Let's call that the service level.