Oracle GlassFish Server 3.0.1 Administration Guide

Resource Statistics (Connection Pool)

By monitoring connection pool resources you can measure performance and capture resource usage at runtime. Connections are expensive and frequently cause performance bottlenecks in applications. It is important to monitor how a connection pool is releasing and creating new connections and how many threads are waiting to retrieve a connection from a particular pool.

The connection pool resources fit into the tree of objects as shown in Resources Tree Hierarchy.

Use the following dotted name pattern for connection pool statistics:

server.resources.connection-pool.statistic

The connection pool statistics are shown in the following table.

Table 8–29 Resource Monitoring Statistics (Connection Pool)

Statistic 

Data Type 

Description 

averageconnwaittime

CountStatistic 

Average wait-time-duration per successful connection request 

connrequestwaittime

RangeStatistic 

Longest and shortest wait times, in milliseconds, of connection requests since the last sampling. current value indicates the wait time of the last request that was serviced by the pool 

numconnfailedvalidation

CountStatistic 

Number of connections in the connection pool that failed validation from the start time until the last sampling time 

numconnused

RangeStatistic 

Number of connections that are currently being used, as well as information about the maximum number of connections that were used (high water mark) 

numconnfree

RangeStatistic 

Number of free connections in the pool as of the last sampling 

numconntimedout

CountStatistic 

Number of connections in the pool that timed out between the start time and the last sampling time 

numconncreated

CountStatistic 

Number of physical connections that were created by the pool since the last reset 

numconndestroyed

CountStatistic 

Number of physical connections that were destroyed since the last reset 

numconnacquired

CountStatistic 

Number of logical connections acquired from the pool since the last sampling 

numconnreleased

CountStatistic 

Number of connections released back to the pool since the last sampling 

numconnnotsuccessfullymatched

CountStatistic 

Number of connections rejected during matching 

numconnsuccessfullymatched

CountStatistic 

Number of connections successfully matched 

numpotentialconnleak

CountStatistic 

Number of potential connection leaks 

waitqueuelength

CountStatistic 

Number of connection requests in the queue waiting to be serviced