eG Monitoring
 

Measures reported by MySQLFileIOTest

This test auto-discovers the top files that are I/O intensive and for each file, reports the wait time and the read/write latency. Using this test, administrators can figure out the file that is experiencing slowness due to high read and write latencies.

Outputs of the test : One set of results for every file in the target MySQL Database instance

The measures made by this test are as follows:

Measurement Description Measurement Unit Interpretation
WaitCount Indicates the number of waits recorded on this file during the last measurement period. Number  
AverageWaitTime Indicates the average time spent by a query per wait to fetch data from this file during the last measurement period. Seconds/Wait  
MinWaitTime Indicates the minimum time spent by a query per wait to fetch data from this file during the last measurement period. Seconds/Wait  
MaxWaitTime Indicates the maximum time spent by a query per wait to fetch data from this file during the last measurement period. Seconds/Wait Ideally, the value of this measure should be low. A sudden/gradual increase in the value of this measure is a cause of concern.

Compare the value of this measure across indexes to identify the file that is experiencing maximum wait time.
AverageReadLatency Indicates the average time taken to read from this file during the last measurement period. Seconds/Read  
MinReadLatency Indicates the minimum time taken to read from this file during the last measurement period. Seconds/Read  
MaxReadLatency Indicates the maximum time taken to read from this file during the last measurement period. Seconds/Read Ideally, the value of this measure should be low. A sudden/gradual increase in the value of this measure is a cause of concern.

Compare the value of this measure across indexes to identify the file that is experiencing maximum read latency.
AverageWriteLatency Indicates the average time taken to write into this file during the last measurement period. Seconds/Write  
MinWriteLatency Indicates the minimum time taken to write into this file during the last measurement period. Seconds/Write  
MaxWriteLatency Indicates the maximum time taken to write into this file during the last measurement period. Seconds/Write Ideally, the value of this measure should be low. A sudden/gradual increase in the value of this measure is a cause of concern.

Compare the value of this measure across indexes to identify the file that is experiencing maximum write latency.