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DB2 for z/OS: Have You Checked Your Log RBA Value Lately?
Pratin Ashtekar 2700046SAG firstname.lastname@example.org | | Tags:  robert_catterall im db2 system_z iod z/os | 5,368 Visits
I was in Las Vegas sometime back for the IBM Information on Demand 2012 conference. At this year's IOD event I'd particularly enjoyed learning more about DB2 11 for z/OS, the beta program for which is expected to begin in March of 2013. DB2 11 will deliver a lot in the way of new features and capabilities.
One of the big news items there was the extended RBA that will be available in DB2 11 systems running in new-function mode (the RBA, or relative byte address, is an identifier for records written by a DB2 subsystem to its transaction log). Whereas the current RBA is a six-byte hexadecimal value, providing 2^48 bytes (256 TB) of log capacity, the DB2 11 extended RBA is a ten-byte value, allowing for the logging of a yottabyte of data-change records. Not familiar with the term, "yottabyte?"
Neither was I until a couple of days ago. It's 1000 zetabytes, or a trillion terabytes. That's a lot of logging capacity. A larger maximum RBA value is important because a few DB2 for z/OS sites have bumped up against the 2^48-byte limit of the current RBA. In this blog entry I have provided information that can help organizations to head off a DB2 for z/OS log RBA limit problem before it occurs.I've spoken more on this in my personal blog that will give you more details & actions you will be interested in.