Allocating a sufficient dump data set size

Because you are dumping multiple address spaces, multiple data spaces, and multiple storage data areas, you may need a much larger dump data set defined than is normally used for system dumps of a single address space. You should preallocate a very large SYS1.DUMPnn data set. For more information on SYS1.DUMPnn data sets, see the DUMPDS command in z/OS MVS System Commands.