Binary Backup with Prepare

Rather than doing the Prepare work to make the database consistent at restore time, the Prepare can be performed by the plugin automatically during the backup phase by adding the plugin option prepare keyword. Prepare has two options fd (default) and sd.

When the prepare=fd option is specified, the prepare will be done on the File Daemon machine at backup time prior to sending the prepared binary data to the Storage Daemon.

Note

Doing the prepare during the backup allows the restore to be done faster (particularly for large databases), but it requires more disk space, CPU and I/O resources. The additional resources might be undesirable if the File Daemon is running on a critical server (see below for a possible solution to this case).

As an alternative to doing the prepare on the File Daemon, it can be done on the Storage Daemon by using the plugin option prepare=sd. With this option there is no additional disk space, CPU or I/O required on the File Daemon. However, the additional disk, CPU, and I/O will be used on the Storage Daemon.

Note

If several File Daemons use the prepare=sd option at the same time, the load on the Storage Daemon can increase significantly. By having robust Storage daemons or several Storage Daemons, one can largely mitigate the extra overhead imposed on them.

It is possible to specify xtrabackup options in /etc/my.cnf in a [xtrabackup] section.

Note

The prepare option (either for the FD or the SD) works only with a Full backup. Incremental or Differential backups cannot use the prepare option.