A common request is to have replication crash-safe in the sense that the replication progress information always is in sync with what has actually been applied to the database, even in the event of a crash. Although transactions are not lost if the server crashes, it could require some tweaking to bring the slaves up again.

In the latest MySQL 5.6 milestone development release, the replication team has implemented crash-safety for the slave by adding the ability of committing the replication information together with the transaction (see Figure 1). This means that replication information will always be consistent with has been applied to the database, even in the event of a server crash. Also, some fixes were done on the master to ensure that it recovers correctly.

If you're familiar with replication, you know that the replication information is stored in two files: master.info and relay-log.info. …

The MySQL Innodb storage engine provides ACID compliance, the ‘I’ being isolation. There are four states defined in MySQL with the tx_isolation system variable, READ-UNCOMMITTED, READ-COMMITTED, REPEATABLE-READ and SERIALIZABLE.

Generally MySQL installations do not modify the default value of tx_isolation = REPEATABLE-READ, however I have seen with a number of clients the default value has been changed to READ-COMMITTED. When I attempt to identify the reason why, I have always received the same reason. Oracle uses a default transaction isolation of READ-COMMITTED. See how Oracle Manages Data …

Well at least your MySQL database world.

As Paul eluded to, PrimeBase Technologies has a project to provide synchronous replication for MySQL in a High Availability environment. It is more then an idea, there is a plan.

Is it possible?
What are the use cases?
How can you use it?
Would you use it?

Some input to date. We need these questions and more, and we seeking more input for discussion.

Unfortunately the opportunity to hear any input during a presentation is left to the last day of the conference, so we have created a BoF session on Tuesday night for a round table discussion if necessary. We encourage people to bring specific cases and situations for feedback, the reasons why MySQL Replication, MySQL Cluster, DRBD/HeatBeat or any other solution does not satisfy your needs, and what …

I’ll be following closely the progression of Storage Engines available in the MySQL Database server, well soon to be available when 5.1 gets to GA (hopefully by end of Q2 which is what we have been told). Tick, Tick, time is running out.

PrimeBase XT (PBXT) and Blob Streaming is obviously my clear focus, actually now working for PrimeBase Technologies, the company which I want to note for people is an Open Source company, committed at providing an open source alternative to the other commercial players. You also have at the MySQL Conference talks on the the existing InnoDB from Innobase (a subsidiary of market RDBMS leader Oracle). There is a …