There are occasions where you may want to re-initialise the AC server. What I mean by this, above all, is for the AC server to flush its internal cache and re-read relevant data, formulas etc. from the file system and RDBMS.

One common scenario during development is that you have changed a formula in the AC Desktop and want to try out the new behaviour. If you want to be certain that during your tests the new version of that formula is used, you should re-initialise the server:

acdba@acbox:~$ ac_init_server
+++INFO+++ 20190318_20:23:12 ac_init_server: Reinitializing 536870932@acbox:
+++INFO+++ 20190318_20:23:13 @(#)ac_init_server_n[7.3/$Revision: 47831 $]: Query Server reinitialization OK
+++INFO+++ 20190318_20:23:13 ac_init_server: Reinitializing 536870931@acbox:
+++INFO+++ 20190318_20:23:14 @(#)ac_init_server_n[7.3/$Revision: 47831 $]: Update Server reinitialization OK

As shown above, this command will re-initialise both the query and update server as well as the replicator if it is running. If you only wanted to re-initialise the query server, you could use the option -q:

acdba@acbox:~$ ac_init_server -q
+++INFO+++ 20190318_20:27:19 ac_init_server: Reinitializing 536870932@acbox:
+++INFO+++ 20190318_20:27:19 @(#)ac_init_server_n[7.3/$Revision: 47831 $]: Query Server reinitialization OK

The options -u and -r will cause the re-initialisation of the update server and replicator respectively.

So, should you find yourself wondering why adding a debug message to a formula seems to have no effect, try to run ac_init_server.