FPEV0136W `<V1>` PERFORMANCE WAREHOUSE IS ACTIVE. THE COMMAND IS IGNORED

Explanation
 This message is issued in response to a MODIFY
command. You tried to start the Performance Warehouse function while
this function is already active.  
<V1> is the Db2 subsystem
ID.

User response
 If you tried to start the Performance Warehouse
function in forced mode, stop it first and then restart it in forced
mode.