| Measurement |
Description |
Measurement
Unit |
Interpretation |
| Pool_availability |
The current state
of a database connection pool – whether it is available or not |
Percent
|
A value of 100
denotes that the pool is available; a value of 0 denotes
unavailability. |
| Pct_conns_used |
Percentage of
database connection allocated to a connection pool that are in use |
Percent
|
When this value
reaches 100%, connections to the database will either have to wait for
access or will time out. Consider increasing the size of the
connection pool in this case. A very high percentage of use can also
result if one or more of the applications that use the connection pool
are not releasing the connections after their use. |
| Max_capacity |
The maximum number of connections configured for a JDBC connection
pool
|
Number
|
|
| Active_conns_current |
The number of connections currently in use for a JDBC connection pool |
Number
|
|
| Waiting_for_conns |
The number of requests for connections to the database that are currently pending |
Number
|
A high value of pending connections is indicative of a bottleneck during database access. Reasons for this could either be that the connection pool capacity is insufficient, or that the database server has slowed down, causing requests to take longer to execute their queries. |
| Active_conns_max |
The high water mark of active connections in a pool |
Number
|
Note the changes in the high water mark. This can give you an idea about the times when the JDBC pool was most heavily used. |
| Waiting_for_conns_max |
The high water mark of number of waiters for a connection from the pool |
Number
|
Note the changes in the high water mark. This indicates periods when the database connection pool could have been a bottleneck. |
| Conns_added_to_pool |
The rate at which JDBC connections were added to the pool |
Conns/Sec
|
|
| Leaked_conns |
The rate of
connections tagged as a leaked connection. A leaked connection is a connection that was checked out from
the connection pool but was not returned to the pool by calling
close(). |
Conns/Sec
|
A non-zero value
indicates that the application may not be releasing connections after
use. This can result in inefficient management of the database
connections in the pool. |
| Failure_to_reconnect |
The rate at which a connection pool
attempted to refresh a connection to the database and failed |
Attempts/Sec
|
Failures could
happen if the database is unavailable, or, the connection was
terminated. |
| Conns_delay_time |
Avg. time taken
to get a connection from the database (in seconds) |
Secs
|
An increase in
this metric could indicate a bottleneck in the database tier. |
| Max_wait_to_get_conn |
The high water mark of the time a thread had to wait in order to get a connection from the pool |
Secs
|
|