in case you are running SP 6 (revision 60 or higher), you might have wondered what the new “compileserver” process is for (one per HANA instance).
The compileserver is needed with SAP HANA SP6 as compiling of L-Procedures has been thrown out of Indexserver.
Without compile server, HANA will not start any more. This is a feature. For customers this is irrelevant, as HANAs default parameters will make sure that it is started. If customers change these defaults, the system is no longer supported.