GSoC Week 4: Extracting memory data values

In this week i started on reading memory values from the system and storing it in memory values table in System Performance and Utilization  module.

Querying the used memory for this is done using the Java Management beans where it expose both use memory and free memory values with MemoryMXBean. The following link is explaining about the structure of the beans API.

http://docs.oracle.com/javase/7/docs/api/java/lang/management/ManagementFactory.html

Once we read memory values from the beans, we store them in the metric_values table. This operation is called in each 10 seconds where it reads used memory value and them sleeps for 10 seconds.

After every one minute the used memory values which was recorded for the previous minute is taken and we get the average used memory value for that minute using these. Then there is another table named per_minute_value_table. The new average used memory value will be recorded in this table in every minute.

Below is the structure of the metric_value table of the new module and how the data entered there looks like for now.

The next step would be read these entries from DB and display them in graphs in the UI.