API GW generates thousands of NoSuchVariableExceptions which slow down API GW due to filling Java call stack

Products

• CA API Gateway

Issue/Introduction

API GW generates thousands of NoSuchVariableExceptions which slow down API GW due to filling Java call stack when under load .

We found that API GW generates thousands of NoSuchVariableExceptions which slow down API GW due to filling Java call stack.

So, we started process how to mitigate these exceptions. We found the defacto the same as mentioned in your document.

1.     Encap. ass. needs all input parameters to be initialized.
2.     Encap. ass. needs all output parameters to be initialized.
3.     Comparison ass. need to compare initialized variables.
4.     Set context variable ass. of type “Message” generates the exception as well.

5      routing assertion when response variable  is not defined 

 

How to avoid:

Ad 1) Initialize parameters in the parent policy or mark parameter as GUI. PM Policy validation is able to find these uninitialized variables.
Ad 2) Initialize parameters internally in encap. ass. PM Policy validation is NOT able to find these uninitialized variables.
Ad 3) Initialize parameters before compare. PM Policy validation is able to find these uninitialized variables.

Ad 4 and 5 ) We cannot find proper solution.

 

Environment

API Gateway 11.x 

Resolution

For the points 4 and 5 we will create a fix which will be included in gateway 11.1.2 

 4.       Set context variable ass. of type “Message” generates the exception as well.

 5.       routing assertion when response variable  is not defined .