IBM z13s, Technical Manual

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Chapter 1. Introducing IBM z13s servers
19
OSM and OSX channel path identifier types
The z13s provides OSA-Express5S, OSA-Express4S, and channel-path identifier (CHPID)
types OSA-Express for Unified Resource Manager (OSM) and OSA-Express for zBX (OSX)
connections:
򐂰 OSA-Express for Unified Resource Manager (OSM)
Connectivity to the intranode management network (INMN) Top of Rack (ToR) switch in
the zBX is not supported on z13s servers. When the zBX model 002 or 003 is upgraded to
a model 004, it becomes an independent node that can be configured to work with the
ensemble. The zBX model 004 is equipped with two 1U rack-mounted SEs to manage and
control itself, and is independent of the CPC SEs.
򐂰 OSA-Express for zBX (OSX)
Connectivity to the IEDN provides a data connection from the z13s to the zBX. OSX can
use OSA-Express5S 10 GbE (preferred) and the OSA-Express4S 10 GbE feature.
OSA-Express5S, OSA-Express4S feature highlights
z13s servers support five different types each of OSA-Express5S and OSA-Express4S
features. OSA-Express5S features are a technology refresh of the OSA-Express4S features:
򐂰 OSA-Express5S 10 GbE Long Reach (LR)
򐂰 OSA-Express5S 10 GbE Short Reach (SR)
򐂰 OSA-Express5S GbE Long Wave (LX)
򐂰 OSA-Express5S GbE Short Wave (SX)
򐂰 OSA-Express5S 1000BASE-T Ethernet
򐂰 OSA-Express4S 10 GbE Long Reach
򐂰 OSA-Express4S 10 GbE Short Reach
򐂰 OSA-Express4S GbE Long Wave
򐂰 OSA-Express4S GbE Short Wave
򐂰 OSA-Express4S 1000BASE-T Ethernet
OSA-Express features provide important benefits for TCP/IP traffic, which are reduced
latency and improved throughput for standard and jumbo frames. Performance
enhancements are the result of the data router function being present in all OSA-Express
features.
For functions that were previously performed in firmware, the OSA Express5S and
OSA-Express4S now perform those functions in hardware. Additional logic in the IBM
application-specific integrated circuit (ASIC) that is included with the feature handles packet
construction, inspection, and routing. This process allows packets to flow between host
memory and the LAN at line speed without firmware intervention.
With the data router, the
store and forward
technique in direct memory access (DMA) is no
longer used. The data router enables a direct host memory-to-LAN flow. This configuration
avoids a
hop
, and is designed to reduce latency and increase throughput for standard frames
(1492 bytes) and jumbo frames (8992 bytes).
HiperSockets
The HiperSockets function is also known as
internal queued direct input/output (internal
QDIO or iQDIO)
. It is an integrated function of the z13s servers that provides users with
attachments to up to 32 high-speed virtual LANs with minimal system and network processor
usage.
HiperSockets can be customized to accommodate varying traffic sizes. Because the
HiperSockets function does not use an external network, it can free system and network
resources, eliminating equipment costs while improving availability and performance.