PQ60163: GROWTH IN ECSA SUBPOOL 231 KEY 6 WITH AFPA ASCII HTTP DATA

Obtain the fix for this APAR.

APAR status

• Closed as unreproducible in next release.

Error description

• Customer experienced a high number of CSM 4K ECSA buffers
  accumulating in subpool 231 Key 6.  The buffers contain
  FRCA or AFPA presend buffers of ASCII data.  The buffers are
  x'400' in length and start with '48545450'(characters: HTTP).
  
  VERIFICATION STEPS:
  1) subpool 231 key 6 is high
  2) largest allocations in VSMDATA will be for x'20000' bytes
  3) the allocations will contain buffers (sometimes every x'400'
  bytes) of ASCII data that start with x'48545450'
  4) SKMB / SKDB message triples can be found that point to these
  buffers but the address of the SKMB is not found on any output
  queue.
  

Local fix

• KEYWORDS: sp231k6 subpool 231 key 6 FRCA AFPA CSM HTTP HTTP/
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of the Communications Server for   *
  *                 OS/390 Release 10 IP and                     *
  *                 z/OS Version 1 Release 2 IP: FRCA            *
  ****************************************************************
  * PROBLEM DESCRIPTION: Storage growth in SP231 K6 when FRCA    *
  *                      presend buffers are not released.       *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  WebServer is enabled for FRCA and is running in an enclave.  A
  connection is serviced from the cache along with a presend
  buffer.  The client sends a reset on the connection before the
  SRB for the WLM process copies the data from the presend buffer
  to the send queue.  The connection delete process clears out
  the uwcx which removes the reference to the presend buffer.
  Later connection cleanup processing no longer has the address
  of the presend buffer which prevents it from being released.
  Storage growth in subpool 231 key 6 occurs as the presend
  buffers accumulate.  Stopping the TCPIP stack will cause the
  orphaned presend buffers to be released.
  +-------------------------------------------------------------+
  + Please check our Communications Server for OS/390 homepages +
  + for common networking tips and fixes.  The URL for these    +
  + homepages can be found in Informational APAR II11334.       +
  +-------------------------------------------------------------+
  

Problem conclusion

Temporary fix

Comments

• Code has been amended to release the presend buffer when the
  connection is reset before the data has been copied to the
  send queue.
  In addition to releasing the presend buffer, a serviceability
  check has been added to the final cleanup process to issue an
  abend4C5 if the presend buffer has not been released.
  

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  UQ66028 UQ66029

Modules/Macros

• EZBAFINB EZBAFSCO EZBAFUTL
  

Fix information

• Fixed component name

  TCP/IP V3 MVS

• Fixed component ID

  5655HAL00

Applicable component levels

• R120 PSY UQ66028

     UP02/06/06 P F206

• R50A PSY UQ66029

     UP02/06/06 P F206

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.