Dynamic Provisioning Delivered Through SOSS
by Hu Yoshida on Nov 6, 2007
This Monday, Hitachi announced the availability of Dynamic Provisioning also known as thin provisioning as a service for heterogeneous storage systems that are attached to the USP V and USPVM. This means that enterprises can now deploy thin provisioning to any system that attaches to the USP V platform. No need to wait for EMC or IBM to deliver it in the distant future on their latest storage platform. You can enjoy it today on your existing storage platforms. Unlike other thin provisioning platforms that are limited to their own proprietary storage system, Dynamic Provisioning can be used to enhance other vendors’ storage products.
What does Dynamic Provisioning do? In open systems, applications must ask for enough disk space to contain their data, before they start writing to disk. In order not to over run their allocated space, application users make it a practice to request more than they believe they need. This over allocation may never be used. Dynamic Provisioning enables the application user to “over provision” their logical volume request with additional capacity, but “thinly provisions” the physical storage with only the capacity that is actually used, eliminating the waste of allocated but unused disk capacity. The “Dynamic” description refers to the ability to allocate additional physical capacity as required, up to the specified logical capacity. The physical capacity is allocated in 42 MB pages that are striped across a pool of logical devices which may span hundreds of disk drives, which reduces the possibility of hot spots due to disk access contention. Besides saving wasted capacity, Dynamic Provisioning simplifies the management tasks of provisioning and performance tuning.
This savings of allocated but unused capacity is magnified by the number of copies that are usually taken of an allocated volume. There may be three to twenty or more copies that are made for backup cycles, data mining, development test, replication, data distributions, etc. Without Dynamic Provisioning, the allocated but unused space would have been copied over and over again. Shadow Image, the ability to create point in time copies is supported for Dynamic provisioning today. Replication services like TrueCopy and HUR will be available later in the years as this feature continues to roll out.
Dynamic Provisioning is an example of Services Oriented Storage Solutions in action. By adding this feature to the USP V virtualization platform, it becomes available as a service to any application that that attaches to the front storage ports, using any vendor’s storage product that attaches through the USP V/VM. You can expect to see future additions to our services catalog, for block, file and content services, all enabled on the USP V/VM platform.
Comments (2 )
I lack a lot of arguments for why. The basic argument is the bad utilization of the the sentralized storage. If it can be documented less then 50 percent, dynamic provisioning is a must. If utilization is above 70 percent, dynamic provisioning is a yawn, a function “Nice to Have”.
One ot the most interesting functions of virtualization og storage must be the ability to pretend the storage is much bigger than it realy is.
This argument was the basic argument for virtualization of memory in computers at the time memory was based on magnetic core. 4 KB pages is still a foundation of memory management.
The other argument should be a discussion about sizes of LUNs. Change of size often requires work at night because of the necessety of IPL.
The argument that applications are not affected is a consequence. Used as an primary argument it disguises the challenge. The result is only seen as extra overtime for the professionals doing the changes when others sleep.
Senior Editor Computerworld Norway
I would like to know if HDP will ever be available on the USP/NSC platform. We have 2 NSC55s which we purchased with the expectation of virtualization and thin provisioning, and we cannot just replace them with USP VMs to get thin provisioning.