Engineering provided additional information on the Call Time (ms) Metric. Looking at 

 https://docops.ca.com/ca-apm/10-5/en/using/apm-webview/collect-and-analyze-transaction-traces

  only says :

  Call time (ms)

  This value displays the length of the call in milliseconds.

  Can I learn some details about the Call Time (ms) metric? 

All supported APM Releases.

   This is how the metric looks like in the Investigator 

<Please see attached file for image>

What is being shown here?

CallTime: A method's own execution time excluding other methods called from that method.

e.g.:

void methodA() {

//some code here

methodB();

//some code here

methodC();

//some code here

}

 So

ART of methodA  = callTime of MethodA + ART of MethodB + ART of MethodC

 where ART = Average Response Time.

If the method takes significantly lesser amount of time than 1 ms, then APM shows as zero.

Org.apache.catalina.connector.RequestFacade:getInputStream

There are a few dummy nodes shown for which there is no logic to execute there to generate call time metric.  Hence, we show them as zero as in the above image for the below node.

Backends|file%customer-records (Hypersonic)