Quantify performance gain when using Java instead of SSJS

Question

When developing XPages applications it seems to have become very popular to mainly use Java methods and beans instead of server-side JavaScript (SSJS). SSJS of course takes longer to execute because the code has to be evaluated at runtime. However, can anyone provide information about the QUANTITATIVE gain in performance when using Java? Are there any benchmarks for how much the execution times differ, for example depending on the length of the SSJS code or the functions used?

Answer 1

You have to use your own benchmarks. The increase in time might not be measurable. It is more around capabilities and your development process. Switching from SSJS to Java an expecting an instant increase in performance most likely won't happen.

Unless of course Java allows you to code things differently. So most of the decisions are based on capabilities, not speed. You are most welcome to run some tests and share the insights. What you can expect e.g. opening a document in SSJS vs. Java: the difference should be in the space of a rounding error, since most of the time is needed for the C call below.

SSJS and Java run at almost the same speed after the SSJS has been evaluated, so you have some onramp time and similar speed thereafter.