RE: Whopping significant disk space on our 520 development lpar.

I have one machine with recent activity (today) and WRKENVVAR LEVEL(*SYS) 
has nothing.

The system that was hog wild has
Name                        Value 
PASE_TZ                     'EST5EDT'
QYPS_SOCKETTIMEOUT          '30' 
QYPS_MAX_CONTIMOUT          '180' 
QIBM_SJ_TRACE               '1' 
QZLC_SERVERLIST             '1' 

I used iNav to drill down and find out who is using the current version in 
that directory.  Job=(957316/QYPSJSVR/QYPSJSVR).

But you're probably right, we have had issues, and do have a couple open 
with IBM regarding Management Central so it is not unlikely that we 
started tracing somehow.  Yes, using this technote:
   Document Number:   354638125
  ____________________________________________________________
  Functional Area:                       Basic System Environment 
Functions
(BSEF)
  SubFunctional Area:               System Management Monitoring
  SubSubFunctional Area:       Management Central
  ____________________________________________________________
  Product:  OS/400 BASE (5722SS100)
  Release:  V5R3M0

  Classification:       Public Use

  Keywords:            MGTC
 ____________________________________________________________
 Document Title:V5R3:  Management Central Tracing
 Document Description:
  V5R3 Management Central Server Trace


Rob Berendt