DS8000 enhancements

When the z10 was announced some three weeks ago, I promised to comment on the related announcements as well. I had some busy weeks so I haven't come around to them yet. But . . . better late than never. As you can see on the poster 'The Future runs on System z' that I posted last week, the subtitle says 'and IBM System Storage'. The z10 goes hand in hand with the DS8000. So what's new for the DS8000 ? In fact there wasn't announced that much as we saw already some major updates last year like e.g. the introduction of Dynamic Volume Expansion, System Storage Productivity Center (SSPC) and Adaptive Multi-stream Pre-fetching (AMP). Still, the novelties are worth mentioning.

First of all the announcement for the DS8000 describes Extended Distance Ficon for IBM System z environments. Due to an enhancement in the FICON architecture standard communication over greater distances is enabled without substantial reduction to the effective data rate. As an example it's said that "it can help keep a 4 Gbps link fully utilized at 50 km". This may "reduce the need for channel extenders in z/OS Global Mirror (2-site) and z/OS Metro/Global Mirror (3-site) configurations". This can mean a substantial cost reduction.

Secondly there's a preview of Extended Address Volumes. This is also explained in the z/OS 1.10 Preview Announcement. As it will require z/OS 1.10 it will only become available in September when z/OS 1.10 becomes available. Today the largest volume counts 65,536 cylinders (54GB). Initially EAV will offer support for up to 262,668 Cylinder Logical Volumes (223GB). At first this will only be for VSAM datasets (including DB2 datasets). But there's an "architectural limit of hundreds of TB per volume". So in the future we may expect to see even larger volumes and more data types supported. At that time the Dynamic Volume Expansion might come in handy. A summary : " This new function is expected to provide substantial, immediate constraint relief for installations with a large number of large VSAM data sets. This is also expected to help improve storage management administration over time, as a relatively small number of large volumes are thought to be simpler to manage than a larger number of smaller ones. IBM recommends the IBM HyperPAV licensed function on the IBM System Storage DS8000 series be leveraged to help manage the number of paths to devices defined as EAV".