eG Monitoring
 

Measures reported by StormWorkerTest

Topologies execute across one or more worker processes. Each worker process is a physical JVM and executes a subset of all the tasks for the topology. For example, if the combined parallelism of the topology is 300 and 50 workers are allocated, then each worker will execute 6 tasks (as threads within the worker).

A topology runs in a distributed manner, on multiple worker nodes. Storm spreads the tasks evenly on all the worker nodes. The worker node’s role is to listen for jobs and start or stop the processes whenever a new job arrives.

This test reports the number of executors and the assigned memory in the worker node. It also monitors the uptime of worker node before users start complaining.

Outputs of the test: One set of results for each Worker in the target Apache Storm.

Descriptor: Worker

The measures made by this test are as follows:

Measurement Description Measurement Unit Interpretation
executorsTotal Indicates the total number of executors in workers node. Number

 

assignedMemOnHeap Indicates the size of assigned heap memory for workers node. MB

As a rule of thumb, there should be enough heap memory to address data processing. If the heap memory is high, then it leads to garbage collection.

assignedMemOffHeap Indicates the size of assigned memory off-heap for workers node. MB

If there is no off-heap memory, then you will be unable to perform the data processing. To avoid this, it would be good practice to allocate adequate off-heap memory.

assignedCpu Indicates the number of assigned CPU core for workers node. Number

 

uptime Indicates the time period that the worker node has been up since the last time this test ran. Hrs/Mins/Secs

The accuracy of this metric is dependent on the measurement period - the smaller the measurement period, greater the accuracy.