Mainframe Storage Economics: Part 2
by David Merrill on Aug 9, 2012
My last blog presented some of the same operational and capital pressures for mainframe that we see most often, on the open systems side of IT. This entry will present some of the key storage architecture technologies (again emphasized and somewhat perfected) from the open systems side and applied to the mainframe storage environment.
By way of disclosure, I am not a mainframe, ZOS or S/390 expert. I grew up in the VAX VMS world in the early 80’s, using these systems for CAD, thermal simulations, printed circuit board design and threat simulations (I was in the military electronics world back then). The correlation of new storage architecture options, such as dynamic provisioning and virtualization, comes from my mainframe-expert colleagues and fellow bloggers Claus and Hu. The principles of storage economics apply to all storage, regardless of the host. The mainframe does have different reactions to some of these technologies, but the result is still a reduction of cost per terabyte, and that is important.
The impact of key, and relatively new,storage technologies are as follows. I will start with controller-based Virtualization for the Mainframe Storage:
- Virtualization can present a lower cost tier to mainframe applications. With typical FICON storage systems, only FC drive types were able to be presented. When controller-based virtualization is connected to the host, subordinate or virtualized arrays can now be seen by the MF host, and this can include low cost modular arrays and NL SAS storage systems. This new lower cost tier of disk can be advantageous to ZOS applications with a big appetite for growth, and where lower cost and lower performance drives can make economic sense
- Virtualized, NL SAS disk has a higher density, so moving significant capacity to this new virtualized mainframe tier can reduce floor space and power costs for larger environments. Depending on several factors, this new tier may even replace some tape capacity for the VTL environment
- With heterogeneous storage assets virtualized and presented to the mainframe environment, an IT department has many more options to flex and share storage arrays between open systems and mainframe. If an asset is retired early from one environment, it can be re-purposed for another, extending the useful life of the asset (sweating an asset)
- Virtualization can enable more variations in terms of cost, performance and availability with virtually any storage array being a candidate for connectivity. Your procurement department will appreciate the expanded options to purchase mainframe capacity from a range of vendors and products that, up until now, has not been available to be purchased for the mainframe
More to come on HDP and tiering in the mainframe in my next blog.
Comments (2 )
I was wondering if you had any reference information regarding the sahring of Mainframe and Open Systems hosted on the same storage subsystem?
My organization is currently investigating this possibility and would like to be aware of any pitfalls or disadvantages to doing this.
We have many customers mixing open and mainframe, supporting both Fibre Channel connected Open-V and FICON connected 3390 mainframe volumes on the same VSP system. It is increasingly common with zEnterprise systems combining mainframe with Intel-based blades, primarily running Linux. Also when you need to support both environments but are looking for the cost efficiency of a single VSP.
The VSP can be configured to facilitate the isolation of different types of data so you don’t have to worry about the two worlds colliding. One limit to be aware of is you can’t mix the two environments in shared pools or cache partitions.
You will find some further information in this whitepaper http://www.hds.com/assets/pdf/why-choose-an-ibm-ficon-switched-network.pdf