What's the difference between MultiProgrammingLevel and CurrentMultiProgrammingLevel?

[Former Member]

In Version 12, what's the difference between the two server properties MultiProgrammingLevel and CurrentMultiProgrammingLevel?

In my testing, they appear to be the same .... executing the command in dbisql:

CALL sa_server_option ( 'CurrentMultiProgrammingLevel', 25 );

changed the value of both properties to 25.

I'm using SA 12.0.1.3152

Thanks!

Margaret

[VolkerBarth · Accepted solution]

Note, this is just a guess:

IMHO, they should have the same value.

MultiProgrammingLevel is an older server property, introduced with V10, and comes from the time when the multiprogramming level was statically fixed at server start time (dbsrxX -gn).

CurrentMultiProgrammingLevel is one of those new properties to check the automatic tuning of the database server multiprogramming level introduced with V12. Others are AutoMultiProgrammingLevel, MaxMultiProgrammingLevel and MinMultiProgrammingLevel.

One might think that for V12, MultiProgrammingLevel could have been omitted (as it seems to have the same meaning as CurrentMultiProgrammingLevel) but was left for reasons of backward compatibility (which would sound reasonable, of course!).

[MarkCulp · Accepted solution]

Volker is correct - I checked the code and both return the same value. MultiProgrammingLevel has been retained for backward compatibility and has been replaced with the newer CurrentMultiProgrammingLevel as a result of the automatic tuning of MPL which was added in 12.

[VolkerBarth · Accepted solution]

Wow, so I did some kind of code review without having the code available? - That can only work since "Watcom does the things the way they should be done.":)