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Working sets and BADPAGFILA bugcheck?

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The Question is:

One of the V6.2 VAX systems I look after crashed today with a BADPAGFILA
I looked this up in DSN and it seems that the real reason for the crash was
 that I'd run out of available balance set slots so VMS decided to bounce one
 of my processes into a swap/page file. The system will crash with a BADPAGFILA
 bugcheck if the chosen
process has a working set quota bigger than 65536 pages. Fair enough; from
 looking at the dump, at the time of attempted outswap the process's quota was
 65539. Moreover, the value for WSQUOTA in SYSUAF for this particular user was
 also far above 65536.
The bit that's confusing me stems from a related article that says "user
 authorisation quotas, WSQUOTA and WSDEFAULT, when greater than 65536, are
 truncated to less than 65536 when the user logs on to the system". From this
 I'd assume that the "too high"
value acquired from SYSUAF has been overridden. When a process is being readied
 for outswap the SWAPPER reduces its working set size back to WSQUOTA - which
 should now be less than 65536, except that it obviously wasn't.
Am I missing a fundamental trick here or does the outswap candidate have some
 additional metadata attached to itself that forces the quota size above 65536 ?
I know the fix to this is straightforward. I just have to increase BALSETCNT
 and/or reduce WSQUOTA ("do you feel lucky, punk ?"), but I'd like to get the
 theory straight.

The Answer is :

  OpenVMS Engineering has no current plans to address this problem
  on OpenVMS VAX due to the complexity of the code change and the
  adverse impact that the change may have on other functionality.
  WSQUOTA should be restricted to 65000.  This further restriction
  precludes the chances of large WSQUOTA values causing a BADPAGFILA
  On-going work in various OpenVMS Alpha releases permits working
  sets of up to 4GB (WSMAX) in V7, and OpenVMS Engineering expects
  to further increase the permitted OpenVMS Alpha working set size
  in future OpenVMS Alpha releases.  (The upper limit on the OpenVMS
  VAX working set size is 32 megabytes.)
  If you wish to further discuss this limit and the particular
  behaviour of the limit (non)enforcement in LOGINOUT and SYSUAF
  and the BADPAGFILA bugcheck, please contact the Compaq Customer
  Support Center directly.

answer written or last revised on ( 31-MAR-2000 )

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