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What is difference between slave and master?
In the master/slave communication model, master is a device or a process that has control over other devices or processes, whereas a slave is a device or a process that is controlled by another device (called the master).
What is MySQL master slave?
MySQL replication is a process that enables data from one MySQL database server (the master) to be copied automatically to one or more MySQL database servers (the slaves). However, general principles of setting up the MySQL master-slave replication on the same machine are the same for all operating systems.
What happens if MySQL runs out of disk space?
Page 408,409 Section 29.2 Bulletpoint 11 says: If you run out of disk space while adding rows to a MyISAM table, no error occurs. The server suspends the operation until space becomes available, and then completes the operation. In reality, mysqld is not dead.
How much space does MySQL take up?
Table 3.1 Required Disk Space
| Platform | Service Manager Minimum Disk Space | Agent Minimum Disk Space |
|---|---|---|
| Mac OS X | 1.2 GB | 700 MB |
| Solaris x86 64-bit | 1.8 GB | 800 MB |
| Solaris Sparc 64-bit | 1.7 GB | 600 MB |
| Free BSD | N/A | 300 MB (the FreeBSD installation does not include a JRE. It is assumed a compatible JRE is present on the system.) |
What can I say instead of master slave?
Alternatives to Master-Slave Terminology Primary and standby. Leader and follower. Conductor and follower. Source and sink.
How master-slave works in MySQL?
Replication works as follows:
- Whenever the master’s database is modified, the change is written to a file, the so-called binary log, or binlog.
- The master has a thread, called the dump thread, that continuously reads the master’s binlog and sends it to the slave.
How do I know if mysql is full?
To check the sizes of all of your databases, at the mysql> prompt type the following command: SELECT table_schema AS “Database”, ROUND(SUM(data_length + index_length) / 1024 / 1024, 2) AS “Size (MB)” FROM information_schema.
How do I free up space in mysql?
The temporary workaround is to clear up some disk space so MySQL can write to the disk and resume the operation. Things that we can do if we face this kind of problems are: Remove unnecessary files. Purge binary logs.
How do I know if MySQL is full?
What happens when MySQL runs out of disk space?
When the MySQL server ran out of disk space, you would see one of the following error in your application (as well as in the MySQL error log): ? ? [ERROR] [MY-000035] [Server] Disk is full writing ‘./binlog.000019’ (OS errno 28 – No space left on device). Waiting for someone to free space… Retry in 60 secs. Message reprinted in 600 secs. ?
Where does MySQL store data on the disk?
MySQL can be configured to store data on different disk or partition. Look at the path as stated in the error to start with. In this example, our directory is located in the default location, /var/lib/mysql which is under the / partition. We can use df command and specify the full path to the datadir to get the partition the data is stored:
Is it safe to delete MySQL replication logs?
For MySQL Replication, it’s safe to delete all logs that have been replicated and applied on slaves. Check the Relay_Master_Log_File value on the server:
How is a defragmentation operation performed in MySQL?
Note that the above DDL operation is performed via online DDL, meaning MySQL permits concurrent DML operations while the rebuilding is ongoing. Another way to perform a defragmentation operation is to use mysqldump to dump the table to a text file, drop the table, and reload it from the dump file.