zHyperLink for the DS8900F overview

zHyperLink works with a fiber connectivity (FICON®) point-to-point or SAN infrastructure to provide low latency connectivity to FICON storage systems.

zHyperLink is a short distance, mainframe-attached link that provides up to 10 times lower latency than high-performance FICON. zHyperLink is intended to speed Db2® for z/OS® transaction processing and improve active log throughput. zHyperLink technology delivers low latency when traditional SAN-attached DS8000® storage systems are used with its complementary short-distance link technology.

Low latencies are provided for read and write operations for storage systems within the 150-meter distance requirement by using a point-to-point link from the z14 to the I/O bay. Low I/O latencies deliver value through improved workload-elapsed times and faster transactional response times, and contribute to lower scaling costs. The implementation of zHyperLink I/O delivers service times fast enough to enable a synchronous I/O model in high-performance IBM Z® servers.

The zHyperLink function includes read and write support for Global Mirror and Global Copy functions.

A full description of zHyperLink is presented in the IBM® Redbooks® publication IBM DS8880 and IBM Z Synergy.

zHyperLink reduces latency by using point-to-point interconnections between an IBM z14® processor and a DS8880 I/O. The reduction in latency helps organizations accelerate their core transaction processes.

Details of zHyperLink capability per model include:
DS8884
Support of four physical zHyperLink connections.
Requirements for support of zHyperLink in DS8884 configurations include:
  • An extra 6-core processor for a total of 12 cores per processor node
    Note: The additional 6-core processor is required exclusively for zHyperLink support and can be ordered only with zHyperLink hardware.
  • I/O enclosure pair PCIe G3
  • Latest version of Licensed Machine Code (LMC) R8.3.3, or higher

Two or four physical zHyperLink connections are supported at the system level.

DS8886
Support of zHyperLink in configurations with 16 or 24 cores per processor node. Configurations with 8 cores per processor node are required to upgrade to 16 or 24 cores per processor node to support zHyperLink.
Requirements for support of zHyperLink in DS8886 configurations include:
  • 16 or 24 cores per processor node
    Note: In 16 core per processor node configurations, two, four, six, or eight physical zHyperLink connections are supported at the system level. In 24 core per processor node configurations, two, four, six, eight, ten, or twelve physical zHyperLink connections can be supported at the system level.
  • I/O enclosure pair PCIe G3
  • Latest version of LMC R8.3.3, or higher
DS8888
DS8888 now supports up to 16 physical zHyperLink connections.
Requirements for support of zHyperLink in DS8888 configurations include:
  • 24 or 48 cores per processor node
    Note: In 24 core per processor node configurations, two, four, six, or eight physical zHyperLink connections can be supported at the system level. In 48 core per processor node configurations, two, four, six, eight, ten, twelve, fourteen, or sixteen physical zHyperLink connections can be supported at the system level.
  • I/O enclosure pair PCIe G3
  • Latest version of LMC R8.3.3, or higher

zHyperLink write operations accelerate Db2 logging for z/OS transaction processing and improve active log throughput.

Restrictions
  • zHyperLink write operations are currently supported only for Db2.
  • Models that support zHyperLink write operations include:
    • DS8884
    • DS8886
    • DS8888
    • DS8900
  • Asynchronous replication (zGlobal Mirror (XRC) and Safeguarded Copy) is not supported for zHyperLink write operations.
The commands that DS8000 provides for zHyperLink operations include: