Galera replicates the data across the cluster in a virtually synchronous fashion. Based on the availability of cluster nodes the type of data transfer can vary. The important factor which decides the type of data transfer required here is the existing write set in gcache. Galera Cluster stores write-sets in a special cache called the … Continue reading Major SST methods In XtraDB / MariaDB Cluster and its supporting files.
Galera is the core tech behind the Percona XtraDB Cluster and MariaDB Cluster. When using the Galera cluster we might have come across multiple files in the data directory beyond the Native MySQL or InnoDB Files. It is always good to understand these files to know what is happening internally. Each file present in the … Continue reading MariaDB/XtraDB Cluster Default Disk Files and its Significance
As the name indicates, an undo log record contains information about how to undo the recent changes by a transaction. When a transaction writes data, it always makes writes on the tablespace files. InnoDB Undo log stores copy of data that is being modified by any current transaction. So, at this point in time if … Continue reading An Overview to InnoDB Undo Log
One problem I have experienced during logical exporting and importing databases is the tools don’t output any progress indicator (or anything at all really) and using the -v (verbose) switch outputs every single MySQL command being run from the import file. As, importing and exporting of databases is one of the most frequent activity being … Continue reading A Linux Tool to Monitor Progress of MySQL Data Imports and Exports.
Monitoring MySQL server has never been an easy task. Monitoring also needs to go through many Complex and difficult queries to get the details. All these problems can be overcome by an excellent command line monitoring tool called “Innotop”. Innotop comes with many features and different types of modes/options, which helps to monitor different aspects … Continue reading Innotop – A Monitoring tool for MySQL