4. EXCEPTIONS › 4.3 Detailed Exception Descriptions › 02026: Extended Storage Swap Migration Rate Exceeds Max

02026: Extended Storage Swap Migration Rate Exceeds Max

FILE: Paging Activity File
SAS FILE NAME: DAYS.SCPPAG01
SOURCE LOCATION: prefix.MICS.USER.SOURCE(DYRMFEXC)

SEVERITY: Impacting            (SEVERITY='I')
MANAGEMENT AREA: Performance   (MGMTAREA='PERFORMANCE')

PURPOSE:  Identify improper use of expanded storage.

RATIONALE:  A page originally sent to expanded storage and
later migrated to auxiliary storage represents unnecessary
system overhead.  The migration is accomplished by moving the
page first to main memory and then to a pagespace data set.
These operations could have been avoided if the page had been
sent to auxiliary storage in the first place.

DEFINITION:  This exception is detected when the swap
migration rate from expanded storage to auxiliary storage
exceeds an installation-specified maximum.

EXCEPTION STATEMENTS:  The SAS statements identifying the
exception situation and describing the condition are stored
in the source member named in SOURCE LOCATION and are
described below:

**  02026 EXTENDED STORAGE SWAP MIGRATION RATE EXCEEDS MAX
*;
IF EXTSTOR='Y' THEN DO;
  RATE=PAGMIG/DURATION;
  IF RATE GT rate THEN DO;
    EXCCODE='02026'; SEVERITY='I'; MGMTAREA='PERFORMANCE';
    EXCDESC1='EXTENDED STG SWAP MIGRATION RATE EXCEEDS MAX';
    EXCDESC2='MIGRATION RATE=' !! PUT(RATE,8.1) !! '/SEC';;
    LINK HIT;
  END;
END;

THRESHOLD MODIFICATION:  The user should modify the rate
value according to the following convention:

rate - The swap migration rate from expanded to auxiliary
storage is specified.  A threshold rate of 4 pages per second
would appear as:

RATE GT 4