I would suggest checking the IMS-L Listserv and the history of this sort of question.
There have been changes to both z/os and IMS access methods over the years. IMS makes heavy use of VSAM shared services once called the VSAM DC option. IMS also has its own zOS access method known as OSAM (Originally Overflow Sequencial Access Method designed to replace ISAM overflow but now used by IMS for something else) These access methods are very z/os service sensitive. The more you use IMS the more you are exposed. I would not pay much attention to ISVs who claim that they run many historicial version of IMS under zos 1.13. They tend not to run them with high volume complex workloads and also do not really do any mesurable work on a day to day basis. Avram Friedman ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
