Silicon Graphics Altix ICE 8000 Series, Краткое руководство пользователя

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Scali Manage TM On SGI
®
Altix
®
ICE System Quick Reference Guide
• "Power Supply" on page 4
• "Four-tier, Hierarchical Framework" on page 5
• "Chassis Manager" on page 6
InfiniBand Fabric
The SGI Altix ICE 8000 series system topology is based on an InfiniBand interconnect.
Internal InfiniBand switch ASICs of the IRU eliminate the need for external
InfiniBand switches. The dual high-speed, low-latency double data rate (DDR)
InfiniBand backplanes built into the IRUs provide for fast communication between
nodes and racks.
An InfiniBand switch blade provides the interface between compute blades within the
same chassis and also between compute blades in separate IRUs. Fabric management
software monitors and controls the InfiniBand fabric. SGI Altix ICE 8000 series
systems are configured with two InfiniBand fabrics, designated as
ib0
and
ib1
. In
order to maximize performance, SGI advises that the
ib0
fabric be used for all MPI
traffic, such as Scali MPI or SGI Message Passing Toolkit (MPT). The
ib1
fabric is
reserved for storage related traffic. The default configuration for MPI is to use only
the
ib0
fabric. For more information on the InfiniBand fabric, see Chapter 3, "System
Fabric Management" on page 43.
Note: The “
ib0
fabric" is a convenient shorthand for "the fabric which is connected
to the
ib0
interface on most of the nodes”. In the case of the storage service node,
there are four interfaces called
ib0
through
ib3
, all of which are connected to the
ib1
fabric (see "Storage Service Node " on page 11).
The SGI Altix ICE system is a distributed memory system as opposed to a shared
memory system like that used in the SGI Altix 450 or SGI Altix 4700
high-performance compute servers. Instead of passing pointers into a shared virtual
address space, parallel processes in an application pass messages and each process
has its own dedicated processor and address space.
Just like a multi-processor shared memory system, an Altix ICE system can be shared
among multiple applications. For instance, one application may run on 16 processors
in the system while another application runs on a different set of eight processors.
Very large systems may run dozens of separate, independent applications at the same
time.
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