IBM z/OS - Manual (Page 25)

25
LPAR Support of OSA-Express
For z990 customers or customers who use the Processor
Resource/Systems Manager (PR/SM) capabilities IBM
offers the Multiple Image Facility (MIF), allowing the shar-
ing of physical channels by any number of LPARs. Since
a port on an OSA-Express feature operates as a channel,
sharing of an OSA-Express port is done using MIF. The
LPARs are defi ned in the Hardware Confi guration Defi ni-
tion (HCD). Depending upon the feature, and how it is
defi ned, SNA/APPN/HPR and TCP/IP traffi c can fl ow simul-
taneously through any given port.
IPv6 Support
IPv6 requires the use of an OSA-Express adapter running
in QDIO mode and is supported only on OSA-Express
features on zSeries at driver level 3G or above. IPv6 is
supported on OSA-Express for zSeries Fast Ethernet,
1000BASE-T Ethernet and Gigabit Ethernet when running
with Linux on zSeries, z/VM V5.1, and z/OS V1.4 and later.
z/VM V4.4 provided IPv6 support for guest LANs.
Performance enhancements for virtual servers
Two important networking technology advancements are
announced in z/VM V4.4 and Linux on z990:
• The high performance adapter interrupt handling fi rst
introduced with HiperSockets is now available for both
OSA-Express in QDIO mode (CHPID=OSD) and FICON
Express (CHPID=FCP). This advancement provides a
more effi cient technique for I/O interruptions designed
to reduce path lengths and overhead in both the host
operating system and in the adapter. This benefi ts OSA-
Express TCP/IP support in both Linux for zSeries and
z/VM.
• The z990’s support of virtual machine technology has
been enhanced to include a new performance assist
for virtualization of adapter interruptions. This new z990
performance assist is available to V=V guests (pageable
guests) that support QDIO on z/VM V4.4 and later. The
deployment of adapter interruptions improves effi ciency
and performance by reducing z/VM Control Program
overhead.