I/O Connectivity

FICON Express8 – exclusively for System z10

FICON Express8
FICON Express8 is the newest generation of connectivity to the storage area networking (SAN). FICON Express8 supersedes FICON Express4, which will be withdrawn from marketing effective October 27, 2009. With its link data rate of 8 gigabits per second (Gbps) and autonegotiation to 2 or 4 Gbps for synergy with existing switches, directors, and storage devices, you now have additional growth opportunities for your SAN. With support for native FICON, High Performance FICON for System z (zHPF), and Fibre Channel Protocol (FCP), the System z10 servers enable you to position your SAN for even higher performance - helping you to prepare for an end-to-end 8 Gbps infrastructure to meet the increased bandwidth demands of your applications.

FICON channel enhancements for System 10

High Performance FICON for System z (zHPF)
zHPF is a performance and reliability, availability, serviceability (RAS) enhancement of the z/Architecture and the FICON channel architecture implemented exclusively in System z10. Exploitation of zHPF by the FICON channel, the z/OS operating system, and the control unit is designed to help reduce the FICON channel overhead. This is achieved with protocol simplification and reduced number of information units (IUs) processed, resulting in more efficient use of the channel. The FICON Express8, FICON Express4 and FICON Express2 features support both the existing FICON architecture and the zHPF architecture simultaneously. zHPF channel programs can be exploited by OLTP I/O workloads – such as DB2, VSAM, PDSE, and zFS – that transfer small (4K) blocks of fixed-sized data. For more information see Performance.

You many also want to refer to the High Performance FICON for System z (zHPF) technical summary for customer planning (PDF, 245KB) technical paper.

High Performance FICON for System z multitrack operations
FICON Express8 and zHPF support multitrack operations, which can help increase system performance and improve FICON channel efficiency when attached to the IBM System Storage DS8000 series. zFS, HFS, PDSE, and other applications that use large data transfers with Media Manager are expected to benefit.

In laboratory measurements, multitrack operations (e.g. reading 16x4k bytes/IO) converted to the zHPF protocol on a FICON Express8 channel, achieved a maximum of up to 40% more MB/sec than multitrack operations using the native FICON protocol.

zHPF and support for multitrack operations is exclusive to the System z10 servers and applies to all FICON Express8, FICON Express4, and FICON Express2 features (CHPID type FC). Exploitation is required by z/OS and the control unit.

zHPF with multitrack operations is available in the DS8000 series Licensed Machine Code (LMC) level 5.4.3.xx (bundle version 64.3.xx.xx) or later with the purchase of DS8000 series feature (#7092).

Previously, zHPF was limited to read or write sequential I/O's transferring less than a single track size (for example, 12 4k byte records or 12x4k bytes/IO).

Resource Measurement Facility (RMF)
RMF has been enhanced to support FICON Express8. RMF is an IBM product designed to simplify management of single and multiple system workloads. RMF gathers data and creates reports that help your system programmers and administrators optimally tune your systems, react quickly to system delays, and diagnose performance problems. RMF may assist you in understanding your capacity requirements. RMF output is used by the zCP3000 tool to assist with your channel consolidation potential.

Extended distance FICON
Extended distance FICON is an enhancement to the FICON architecture designed to help avoid degradation of performance at extended distances by implementing a new protocol for "persistent" information unit (IU) pacing. Improved IU pacing can help to optimize the utilization of the link, for example to help keep a 4 Gbps link fully utilized at 50 km, and allows channel extenders to work at any distance, with performance results similar to that experienced when using emulation.

ESCON Statement of Direction

ESCON channels to be phased out
It is IBM’s intent for ESCON channels to be phased out. System z10 EC and System z10 BC are to be the last servers to support greater than 240 ESCON channels.

Linux on System z support for XIV

In April 2009, IBM announced support of Linux on System z (Novell SUSE SLES 10 SP2) on IBM XIV Storage System - a revolutionary open disk system that represents the next generation of high-end disk storage, offering self-tuning and self-healing for consistently high performance and reliability as well as management simplicity and low total costs.

The XIV Storage System is compatible with the System z10 FICON Express8 channel (CHPID type FCP for attachment to SCSI devices) autonegotiating to 4 Gbps when attached to a supported FICON/FCP director or switch. System z10, FICON Express8, and Linux on System z combined with the phenomenal capabilities of XIV Storage System can help support today's fast-growing, dynamic environments.

Requisites, code levels, restrictions, and further information regarding XIV Storage System can be found at: http://www-03.ibm.com/support/techdocs/atsmastr.nsf/WebIndex/TD105187