MySQL probe MYSQL_INNODB_CACHE_HIT_RATE
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MySQL probe MYSQL_INNODB_CACHE_HIT_RATE

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Article ID: 275383

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Updated On:

Products

DX Unified Infrastructure Management (Nimsoft / UIM) CA Unified Infrastructure Management On-Premise (Nimsoft / UIM) CA Unified Infrastructure Management SaaS (Nimsoft / UIM)

Issue/Introduction

Can you tell us what the "MYSQL_INNODB_CACHE_HIT_RATE" probe corresponds to and what command is launched

We believe the following command is issued:

SELECT table_name, avg_row_length, data_length, max_data_length, index_length, data_free, table_schema
FROM information_schema.tables
WHERE TABLE_TYPE = 'BASE TABLE'
AND max_data_length > 0 ORDER BY table_schema ASC

If this is the one, it is incorrect because the max_data_length column is not used for the Innodb storage engine:

Info: https://dev.mysql.com/doc/refman/8.0/en/information-schema-tables-table.html

Environment

  • Release: 20.4

Resolution

For the MYSQL_INNODB_CACHE_HIT_RATIO we are not using any query, we are capturing the values from the commands below and calculating the buffer ratio.

   show global status;

   show variables;

This will not cause any issues.