Datapower appliance memory usage
Datapower appliance memory usage statistics are very confusing to note for. When we navigate to WebGUI console and check the memory usage, then it will list us with the following details,
Memory usage
Total memory
Used memory
Free memory
Requested memory
Hold memory
Reserved memory
Installed memory
There is a detailed information given to each value in Datapower appliance.
| Usage | Description | |
| Memory usage | Percentage of memory that is current in use. The instantaneous memory usage as a percentage of the total memory. | |
| Total memory | Installed Memory – Reserved Memory | The total memory of the system in kilobytes. The total memory equals the amount of installed memory minus the amount of reserved memory. |
| Used memory | Total Memory – Free Memory |
The amount of memory that is currently in use. The used memory equals the amount of total memory minus the amount of free memory. The used memory does not include any hold memory. |
| Free memory | The amount of memory that is currently not in use and is therefore available. The free memory value includes any hold memory that is not currently in use. | |
| Requested memory | The amount of memory that has been requested. Requested memory is not reported as used memory until the memory is actually in use. | |
| Hold memory | The amount of memory that is reserved by the appliance itself. | |
| Reserved memory | Installed Memory – Total Memory |
The reserved memory equals the amount of installed memory minus the amount of total memory. |
| Installed memory | The amount of physical memory in the appliance. |
We always look at Memory usage in percentage but there are other attributes that essentially make up the entire memory consumption process in DataPower.
There is a Webcast that explains us about Memory consumption, http://www-01.ibm.com/support/docview.wss?uid=swg27040058 Please go through the webcast to get a better understanding.
There is one more Developer Works article that explains Resource management in Datapower.