What Is perfdump in Android?
What Can be Monitored with perfdump? How To Enable the perfdump SAF Procedure?
You might be wondering what is perfdump in Android. The perfdump function could be defined as a “service” function built-in to the operating system.
The perfdump function is able to collect various pieces of performance data from the web server’s internal statistics and display them in an ASCII format when a specific request is issued for it.
Being a Server Application Function (SAF) built into Web Server its job is to collect various pieces of performance data from the Web Server internal statistics.
SAF is otherwise known as Server Application Functions and is usually built into operating systems with the purpose to perform the necessary steps in order to generate an HTTP request-response.
The SAF functions take the request, and use it alongside the server configuration database as input, and return a response to the client as output with the set of functions applied is determined by the inputs.
SAF has a special class corresponding to the request-response step it helps implement, this being an extra class of application function, known as the initialization function that is executed upon server startup and that is meant to perform static data initialization for the various server modules.
What Can be Monitored with perfdump?
Server application functions usually have a single class and are not informed by the server which class they are being used for, as the server keeps an internal table of available functions, and makes sure to map the function pointers to unique character strings which identify them, therefore through its use of string in the configuration database, a function can be called to carry out one of the above steps.
It’s possible to create custom Server Application Functions (SAFs), this allowing you to modify or extend the Sun Java System Web Server’s built-in functionality like the server to handle user authorization in a special way or generate dynamic HTML pages based on information in a database.
It’s important to know what is perfdump in Android as this type of Server Application Function (SAF) is built into a Web Server with the purpose to collect various pieces of performance data from the Web Server’s internal statistics and display them in ASCII text.
The perfdump output is not able to display all the statistics available through the command-line statistics or the Admin Console, but it can still be a useful tool, as for example, you can use perfdump even if the Administration Server is not running.
You can visualize the perfdump output through the CLI, which is enabled by default, or you can see the perfdump output through a URI, which you might need to enable. If you enable the URI, you must control access to the perfdump URI, otherwise, it can be visible to users.
Perfdump offers statistics that are unified, therefore rather than monitoring a single process, statistics are multiplied by the number of processes, which offers you an accurate view of the server as a whole.
How to Enable the perfdump SAF Procedure?
You can request the perfdump statistics and also specify the frequency that you want the system to automatically refresh its measurements.
To Enable the perfdump URI from the CLI
1. Use the following command to enable perfdump:
./wadm enable-perfdump –user=admin-user –password-file=admin-password-file [–uri=uri]–config=config-name–vs=virtual-server-name
Use the uri option to set the pefdump URI.
2. Deploy the configuration using the wadm deploy-config command.
3. To access perfdump, access the URI on the virtual server.
For example http://localhost:80/.perf
You can ask for the perfdump statistics and specify how frequently the browser should automatically refresh as measured in seconds.
To View the perfdump Data from the CLI
The URI is not the only way in which you can access perfdump. This can be accessed also through the command-line interface, which is enabled by default.
Keep in mind that unlike viewing perfdump output through the URI, the Administration Server must be running to view perfdump output at the command line.
If request processing threads are hanging in your server and you cannot use the URI, you can still access perfdump output through the CLI.
To view the perfdump output through the command-line interface, type in the below formula and the output will show up in your command window.
./wadm get-perfdump –user=admin-user –password-file=admin-password-file –config=config-name –node=node-name
I hope I answered the question of what is perfdump in Android. And remember – the perfdump output will not display all the statistics available through the command-line statistics or the Admin Console, but it still is a useful tool as you can use it even if the Administration Server is not running.