Extended minidump data set (XDUMP)

XDUMPs are enabled by default using the data set name pattern: 
IDIXDPHQ.XDUMP.&SYSNAME..D&YYMMDD..T&HHMMSS..S&SEQ.
To change this data set name pattern, see "Specifying the extended minidump data set name pattern (XDUMPDSN)" . Fault Analyzer allocates the data set with RECFM=FBS LRECL=4096 and uses the access authorization mechanism described in Managing XDUMP data set access. If XDUMP data set allocation fails, Fault Analyzer issues message IDI0184W.

An extended minidump data set (XDUMP) is a Fault Analyzer specific data set that is sometimes created to hold certain types of storage pages and which is tightly coupled with a fault entry. The usage of the XDUMP data set, and its final disposal, is normally transparent to the user.

An XDUMP data set is designed to contain:
  • 64-bit storage pages
  • Application storage that is not directly involved with essential aspects of the analysis, such as program linkage or the point of failure

"Spilled" minidump pages require an XDUMP data set to save 64-bit storage pages and associate them with a fault entry. 64-bit storage pages are not included in a minidump.

For 24-bit and 31-bit applications, an XDUMP data set can provide relief from re-analysis storage constraints.

If the MaxMinidumpPages option value in effect is exceeded during real time processing, the number of pages in excess of the MaxMinidumpPages value are written ("spilled") to the XDUMP. This prevents the issue otherwise resulting in message IDI0133W. However, it also creates a dependency on the XDUMP data set, which must continue to exist for correct reanalysis to occur. This is generally not an issue since the XDUMP should only be deleted automatically by Fault Analyzer when the fault entry is deleted.

If pages are spilled to the XDUMP data set during real time analysis, message IDI0194W is issued.

If an XDUMP data set containing spilled pages is not available during reanalysis, warnings will be issued. For batch reanalysis, message IDI0195W is also issued.

XDUMPs are enabled by default. To test that XDUMPs have been configured correctly, see Verifying the use of XDUMPs.