MySQL Server Buffer Pool Hit Percent Monitor Monitor

  • ID:  Microsoft.MySQLServer.ManagedServer.Unix.InnoDB_BufferPool_HitPct.Monitor
  • Description:  MySQL Server Buffer Pool Hit Percent Monitor
  • Target:  Monitored MySQL Server (Linux)
  • Enabled:  On Standard Monitoring

Operational States

Name State Description
Over Threshold Success Over Threshold
Under Warning Threshold Warning Under Warning Threshold
Under Error Threshold Error Under Error Threshold

Overridable Parameters

Parameter Name Default Value Description Override
Interval 300 Interval in seconds
Number of Samples 3 Number of Samples
Warning Threshold 95 Warning Threshold
Error Threshold 90 Error Threshold

Alert Details

Monitor State Message Priority Severity Auto Resolution
Under Warning Threshold (Warning) MySQL Server InnoDB Buffer Pool Hit Percent Medium Match Monitor Health Yes

Run As Profiles

Name
Default

Monitor Knowledgebase

Summary

The percent of hits MySQL is able to satisfy from the buffer pool versus disk. The innodb buffer pool contains least recently used index blocks. The buffer pool size is controlled using the global variable ‘innodb_buffer_pool_size’. The monitor threshold is analyzed against an average of values returned in polls to the agent where the Number of Samples parameter controls the number of samples included in the calculation of the average.

Causes

An unhealthy state indicates the percentage of reads from the buffer pool versus total reads is low. The buffer pool might not have enough space to hold all inserted blocks.

Resolutions

To address low buffer pool hit percent try the following options:

  • Increase the size of the InnoDB buffer pool by modifying the variable ‘innodb_buffer_pool_size’ in the configuration file.

  • Divide the buffer pool into separate instances for concurrent memory read and write operations by modifying the variable ‘innodb_buffer_pool_instances’ in the configuration file.

External References
This monitor does not contain any external references.

See Also for Open Source Software Preview Management Pack


Downloads for Open Source Software Preview Management Pack

AZURE OPTIMIZATION ASSESSMENT GET STARTED
MIGRATION TO AZURE GET STARTED
SYSTEM CENTER MIGRATION TO AZURE GET STARTED
MIGRATION TO AZURE FOR SQL AND WINDOWS 2008 GET STARTED