Friday, November 21, 2008

MySQL 6.0.8 Feature: Interface for Semi-synchronous Replication

MySQL 6.0.8 has new interfaces for semisynchronous replication.

The interfaces make it possible to load components to ensure that all transactions are replicated to the slave before the users of the master gets acceptance of the commits.

The original code was developed by Mark Callaghan (Google) and Wei Li (Google). Zhenxing He (MySQL) ported the Google code to MySQL 6.0, extracted the functionality into pluggable components, and changed the code so that all storage engines are supported. Paul DuBois (MySQL) wrote the MySQL manual documentation.

The extraction of this patch into components is a first step in our strategy to make MySQL Replication modularized with separate loadable components for special replication functionality. With more interfaces to the server, it becomes easier to make the server behave in the way you want.

Please let us know what you think. Does it work as you expect? Do you want the synchronization to be different? Want to publish your own replication components for MySQL?


Tuesday, November 4, 2008

MySQL Feature Preview: mysqlbackup program

The mysqlbackup client program is now available for download as a feature preview. This program gives information about the produced backup image files and is a complement to the new MySQL 6.0 Backup feature. The program is not yet part of the main MySQL server releases.

So far, we have implemented the first milestone of WL#4534, e.g.:
  • Display metadata contained in backup image (i.e the SQL statements)
  • List objects contained in the backup image
  • Display statistics about the backup image (e.g. compression algorithm)
  • Search and display objects of backup image
  • Search and display metadata of backup image objects
  • In case of problems with reading the image provide as much information
    as possible, e.g. the position of the failure
The current preview handles charsets, databases, tables, and views only. Other object types will follow soon.

Links for Linux and Windows binary download are on the Backup Forge Page.

Please try it out and let us know what features you are missing or you would like to see. Thanks Ingo for great work on coding this.