D STOR shows overflows but no single Slot has any failure.

Products

• TPX - Session Management
• Vman Session Management for z/OS

Issue/Introduction

Why can it be that Command "D STOR" shows Overflows but no single Slot has any failure?

Environment

z/OS

Resolution

It might happen that there is a difference in the Output of Command D STOR - the number of Overflows is a non-zero number but there is no single Failed Slot Request like in this example:

APU2ETPX - ****************** TPX Operator ************************* TEN0217

                             Storage Statistics (Below 16M line)

Open ACBs:  0342     Total ACBs:  1665   Terminals: 0179  Applications: 0702

DSA  Bytes: 04440064 Current Use: 005 %  High Use:  006 % Free Areas:   0006

Slot Bytes: 01441600 Current Use: 000 %  High Use:  002 % Overflows:   03541

 

Slot   Size * Count = Bytes         Curr.Use   Max.Use Failed Requests

01     00016  1024    16384           000 %     000 %  0      169363

02     00024  680     16320           000 %     000 %  0      223109

03     00032  1920    61440           000 %     006 %  0      22498

04     00064  2560    163840          001 %     001 %  0      40436

05     00072  1080    77760           000 %     000 %  0      4311

06     00104  2008    208832          000 %     000 %  0      69783

07     00128  928     118784          000 %     000 %  0      15917

08     00512  928     475136          000 %     000 %  0      870202

09     01024  56      57344           000 %     008 %  0      37530

10     02048  40      81920           000 %     010 %  0      247378

11     04096  8       32768           000 %     037 %  0      46869

12     08192  16      131072          000 %     006 %  0      4069

***************************** BOTTOM OF DATA **************************

 

This discrepancy can occurr if TPX need a Slot of a size even Slot Pool 12 cannot deliver. If you for example define 8192 as the largest Slotsize but the MAIL file has a size of 10240 then TPX need to take the 10240 bytes needed from the DSA instead of the Slot Pool. This is not a Failure to get a Slot of Pool 12 but it is a failure to get any Slot. So TPX does mark this request as an Overflow and displays it in field "Overflows:". The above display shows that Slot 12 is not large enough to fulfil Requests for TPXMAIL. Solution is to enlarge this Slot in the second panel of SMRT and restart TPX. Then this behaviour will no longer appear.

 

Additional Information

You may check the size of your TPX flies in the JES-Log: Messages TPXL0704 show the length of the Records at the end in Parameter B=:

 

TPXL0704 11/13/16.318 03:01:46.51 OPEN successful for VSAM DD VIEW B=08192

TPXL0704 11/13/16.318 03:01:46.53 OPEN successful for VSAM DD NOTES B=04096 

TPXL0704 11/13/16.318 03:01:46.53 OPEN successful for VSAM DD ADMIN1 B=08192 

TPXL0704 11/13/16.318 03:01:46.53 OPEN successful for VSAM DD MAIL B=10240 

 

TPXL0704 11/13/16.318 03:01:46.55 OPEN successful for VSAM DD ADMIN2 B=02048