This post discusses SORTHEAP DB2 and pinned pages Information message in db2diag.log

FUNCTION: DB2 UDB, buffer pool services, sqlbKeepPagesPinned, probe:20
MESSAGE
: ADM6071I  The maximum number of pinned pages allowed concurrently was
          reached in buffer pool "MYBUF8K" (ID "2").  As a result performance
          may not be optimal. Increasing the SORTHEAP database configuration
          parameter may reduce the chances of this condition occurring in the
          future.

Notes

1)  The message refers to the  sqlbKeepPagesPinned  function.

2)  The message indicates the specified buffer pool is too small for current activity.

3)   This also points to high CPU usage

4) Recommend index analysis focusing on indexes using the sort heap.Including hash join buffers, in memory tables, dynamic bitmaps

5) If  SORTHEAP isn’t set at AUTOMATIC , increase the level if large sorts are used.

See Also

DBA Interview Questions and Answers – DB2 Server Operations