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DS8880 zHyperLinks™ Building a strong foundation

By Archive User posted Sun April 16, 2017 02:16 AM

As we said in part 1 of this blog, IBM issued a Statement of Direction for zHyperLink™, on January 10th , for the first new mainframe I/O Channel link technology since FICON®.
zHyperLink is a latest technology that can be installed on existing IBM DS8880 Storage Systems®. The hardware capability is already included in the DS8880 R8.2 Storage Systems and is intended to speed up DB2® for z/OS transaction processing and improve active log throughput.

IBM storage has delivered on a cadence of new I/O technologies over the last few years to address the need for improved I/O latency for storage. These technologies include:

  • Advances in High-Performance Flash Enclosures [Gen2]

  • Fiber Channel 16 Gbs Host Adapters with forward error correction codes to reliably [reduce most I/O latency by 20 percent]

  • Enhanced write protocols for High Performance FICON [zHPF™]

  • SuperPAV-Alias Tuning to [reduce IOS queueing times]

  • The DS8000 DB2 Castout Accelerator ™ for [up to 5x I/O service time reduction] for DB2 cast out (and all z/OS scattered write operations)

  • IBM zHyperWrite™ technology designed to mitigate the elapsed time impact of synchronous replication technologies, [reducing DB2 commit latency by up to 66 percent]

  • FICON Dynamic Routing support in the DS8000 for the z13] and improved caching algorithms that can improve the average I/O service times by increasing read cache hit ratios.

  • As new technologies are deployed in transport, memory, and devices new opportunities are created for innovative system architectures to deliver value to IBM mainframe clients.

    The IBM zHyperLink™ Technology

    The IBM zHyperLink™ technology is a new mainframe attach link. It is the result of collaboration between DB2 for z/OS®, the z/OS operating System, z Systems processors, and DS8880 storage to deliver extreme low latency I/O access for DB2 for z/OS transaction processing and improve active log throughput.

    The DS8880 R8.2 (models 984, 985, 986, and 988) available in 4Q2016, contains the hardware intended to support this technology. IBM also intends that DS8880 models that shipped prior to December 2016 get concurrently field upgradeable for zHyperLinks.
    The zHyperLink is a point-to-point optical connection between the mainframe and storage. The link length is limited to 150 meters, which is the same distance supported by the z Systems short distance coupling technology.

    Client Value

    The client benefits of IBM zHyperLink™ technology are:

  • Accelerating transaction processing on the mainframe

  • Reducing batch elapsed times by providing faster index splits for DB2™ for z/OS. Index split performance is the main bottleneck for high volume INSERTs, resulting in faster Batch Processing

  • Avoiding additional application development cost often required to meet scalability requirements

  • Avoiding additional hardware cost and data sharing instances to meet scalability requirements

  • Benefitting from industry leading I/O latency with an easy to deploy and manage I/O technology

  • Enhancing system resilience through better handling of unpredictable workload spikes and hardware failures

  • Conclusion

    The IBM DS8880 is designed from the casters up for extensibility, client invest protection, and availability. The IBM zHyperLink™ technology is intended to make z/OS a more attractive platform for deploying new workloads, for growing heritage workloads with improved scalability and leveraging reuse of existing storage assets. Issuing the statement of direction allows clients to plan their machine rooms, disaster recovery strategy, and application deployment choices in anticipation of this new technology.

    Harry Yudenfriend

    Peter Sutton




    Fri December 01, 2017 06:32 PM

    There is no need to back the storage system with Flash to get good latency gains, but you do need a good storage based cache hit ratio. Above 90%. This is common with enterprise class storage systems.

    Fri December 01, 2017 06:07 PM

    Just to be clear, the use of Flash is not critical. The random read cache hit ratio is important.
    Flash helps in that it allows to resolve cache misses faster than spinning disk.

    Fri December 01, 2017 05:45 PM

    All reads and writes come from DRAM cache on the DS8880.
    Flash helps to mitigate the elapse time for a cache miss.
    The vast majority of z/OS clients experience very good random read cache hit ratios (over 90%).
    All clients should consider the use of zHyperLinks.

    Fri December 01, 2017 05:33 PM

    Thank you for the feedback!

    Tue November 07, 2017 12:31 PM

    do we have any requirements/recomendations for disk arrays that will provide data to z System using HyperLinks?
    It is justified to connect to non-all-flash disk arrays?

    Fri October 27, 2017 04:48 PM

    This message was posted by a user wishing to remain anonymous
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    Sat August 26, 2017 01:05 AM

    Neat article. Thank you for putting this up.