| Measurement |
Description |
Measurement
Unit |
Interpretation |
| Percent_heap_used |
The percentage of memory utilized by the JVM |
Percent
|
A high value of this measure indicates a heavy workload on the WebSphere application server. In such a case, you might want to consider increasing the JVM heap size.
|
| Free_memory |
The amount of memory currently available in the JVM |
MB
|
A very low value of this measure is indicative of excessive memory utilization in the JVM. |
| Used_memory |
The amount of memory that has been currently utilized by the JVM |
MB
|
A high value of this measure indicates a heavy workload on the WebSphere application server. In such a case, you might want to consider increasing the JVM heap size. |
| GC_Count |
The number of GC calls since the last measurement period |
Number
|
If adequate memory is not allotted to the JVM, then the value of this measure would be very high. A high value of this measure is indicative of a high frequency of GC. This is not a good sign, as GC, during its execution, has the tendency of suspending an application, and a high frequency of GC would only adversely impact the application's performance. To avoid this, it is recommended that you allot sufficient memory to the JVM.
|
| Percent_GC_time |
The percentage of time spent on GC |
Percent
|
If adequate memory is not allotted to the JVM, then the value of this measure would be very high. This is not a good sign, as GC, during its execution, has the tendency of suspending an application, and a high value of this measure would only adversely impact the application's performance. To avoid this, it is recommended that you allot sufficient memory to the JVM.
|
| Objects_allocated |
The number of objects allocated in the heap since the last measurement period |
Number
|
|
| Objects_freed |
The number of objects freed in the heap since the last measurement period |
Number
|
|
| Objects_moved |
The number of objects in the heap since the last measurement period |
Number
|
|
| Threads_started |
The number of threads started since the last measurement period |
Number
|
A high value is indicative of high server workload.
|
| Threads_ended |
The number of threads that ended since the last measurement period |
Number
|
|
| Waits_for_lock |
The number of times a thread waits for a lock, since the last measurement period |
Number
|
|
| Wait_for_lock_time |
The average time a thread waits for a lock |
Secs
|
|