All about kernel mode introduced in ASE 15.7

What is the Kernel Mode? 

First things fist :) Adaptive Server supports only threaded mode on the Windows platform.

kernel mode determines the mode the Adaptive Server kernel uses, either threaded or process. 

In threaded mode, Adaptive Server uses operating system threads to support Adaptive Server engines and specialized tasks. In this mode, Adaptive Server is a single process running on the operating system, which is the new mode introduced in ASE 15.7. 

In process mode, Adaptive Server uses individual processes to support Adaptive Server engines. In this mode, each engine is a distinct process running on the operating system. The process mode is the same kernel used by Adaptive Server versions earlier than 15.7.

The values for kernel mode are character data, so you must use 0 as a placeholder for the second sp_configure parameter, which must be numeric, and specify threaded or processas the third parameter.

• Sybase assumes you use threaded mode in your production server, and includes process mode for backward compatibility. Process mode may not support features for Adaptive Server 15.7 and later.
• BTW, this configuration parameter is STATIC.
• global variable @@kernelmode Returns the mode (threaded or process) for which Adaptive Server is configured.

more info in the blog of  Mr. Andrew Melkonyan (Thanks much sir for the excellent explanation indeed)

https://blogs.sap.com/2013/02/11/ase-157-threaded-vs-process-kernel-mode/