Metadata Lock

Table of contents

• Review
• One month later
• Size of the tables
• Process list
• Global variables
• Metadata Lock and InnoDB Transaction Lock
• Global status

Review

After we introduced dbstat for MariaDB (and MySQL) a good 5 weeks ago, we naturally also rolled it out on our systems to test the behaviour in daily use (eat your own dog food).

This went quite well until we came up with the idea of activating dbstat on the passive dbstat node on our MariaDB active/passive master/master replication cluster (a similar …

Table of contents

• Functionality of dbstat
• How does dbstat work
• How to install dbstat
• Query dbstat
  • table_size
  • processlist
  • trx_and_lck
  • metadata_lock
  • global_variables
  • global_status
• Testing
• Sources

An idea that I have been thinking about for a long time and have now, thanks to a customer, finally tackled is dbstat for MariaDB/MySQL. The idea is based on sar/sysstat by Sebastien Godard:

sar - Collect, report, or save system activity information.

and Oracle Statspack:

Statspack is a performance tuning …