As the size of database and the volume of transactions increase, many of Db2 transactions tend to spend significant amount of wait time in database read and log write I/Os. zHyperLink is introduced to help reduce b2 transaction latency. zHyperLink is a new short...
Last week we ended with Db2 Performance of zHyperLink Read. Now let’s look at the CPU cost of zHyperLink read. As explained last week, I/O operation is now synchronous to CPU with zHyperLink and SQL processing spins while waiting for the I/O to complete. At the same...
For the first time ever, we have five generations in the workplace at the same time. This is most profound in a technology like the Mainframe. Fortunately, today a lot of Organizations realize the importance of training the millennials with the aging mainframe...
Google, Facebook, and Twitter own giant data centers all over the planet, and they are built with racks of commodity hardware. If thousands upon thousands of small servers networked together are good enough for Google, Facebook, and Twitter, then shouldn’t they be...
Not long ago, a Db2 for z/OS administrator contacted me with a request. His team had made some changes to the buffer pool configuration in their production Db2 environment (the overall size of the buffer pool configuration was increased to reduce read I/O activity,...
I have written a few entries for this blog in which I provided information about Db2 for z/OS buffer pools defined with PGSTEAL(NONE), including one from a few years ago in which I differentiated the PGSTEAL and PGFIX buffer pool specifications, and another...
Back in 2014, I posted an entry to this blog on the topic of getting to universal table spaces from non-universal table spaces. In that entry, I noted that there was an online path (ALTER followed by online REORG) for getting from a “classic” partition…
Sometimes, a DBA will email me a question about Db2 for z/OS, and I’ll respond in a pretty comprehensive way, and I’ll look at that outbound message and think to myself, “Hmm. I may have written most of a blog entry there.” This is one of those ca…
Last month, I posted to this blog an entry on the long-awaited capability to migrate tables, in an online way, from a multi-table segmented or simple table space to multiple single-table partition-by-growth table spaces (a capability delivered with fun…
The distributed data facility (aka DDF) is the component of Db2 for z/OS that enables data access by applications that connect to Db2 via TCP/IP communication links. DDF has been around for over 30 years, but especially during the past 10 years or so D…
