SMAPP is killing our 520

Installed brand-spanking new 520 running V5R4 and current PTFs to use for a 
data conversion process.  Data conversion is the only thing running on the 
system so it gets 70-80% of CPU.  Suddenly the data conversion job drops to 
20-30% of CPU but nothing is evident on WRKACTJOB to account for the change. 
We start iNav system monitor and see JO-EVALUATE-TSK1 and JO-EVALUATE-TSK2, 
each taking between 40 & 50 % of CPU.  These jobs don't just run for a 
minute or two and go away, they run for quite a while, and are (the best I 
can tell) related to determining something or other related to SMAPP (System 
Managed Access Path Protection).

My question: What can be done so that the conversion process (which already 
takes several days) doesn't turn into something that takes several weeks and 
the JO... jobs don't suck all of the life out of this new system?  The 
system is new out of the box and has had no special modifications such as 
additional ASPs or user ASPs, etc.  It is currently using 48% of 6 TB DASD 
and 16 GB memory.

TIA,

Steve