Itanium2

From a performance point of view, IA64 technology represents an important improvement compared to INTEL IA32 Xeon standard architecture. IA64 architecture is better adapted than the IA32 to high performance computation particularly for its performances in floating point arithmetic.

Among its assets, IA64 has a greater number of units of execution, performs a greater number of instructions per clock cycle. But the main interest of such architecture lies especially in its memory in term of addressing and size: With a 32 bits Intel architecture (IA32), a program cannot address more than 4 gigabytes (32 bits) of memory whereas IA64 technology can address several exa-bytes (2^60) that is to say some gigabytes of terabytes !

Despite all these theoretical advantages, the validation of this new type of architecture is far from being completed for the high-performance scientific computation community. Thus a new challenge arises: how to exploit the capacities of such a machine as best as possible?

Node description

• 100 nodes with 2 x 900Mhz Itanim2 cpu (ita1 to ita100)
  • 3 Gbytes memory each
  • 36 Gbytes Hard Disk space mounted on /
  • 36 Gbytes Hard Disk space mounted on /scratch (rw for all)

• 1 server with 2 x 900Mhz Itanim2 cpu (ita.imag.fr)
  • 3 Gbytes memory
  • 36 Gbytes Hard Disk space mounted on /
  • 36 Gbytes Hard Disk space mounted on /scratch (rw for all)
  • 700 Gbytes Hard Disk raid5 space for users homedir

• 1 server with 2 x 900Mhz Itanim2 cpu (ita104)
  • 12 Gbytes memory
  • 36 Gbytes Hard Disk space on /
  • 36 Gbytes Hard Disk space on /scratch (rw for all)

• 2 servers with 2 x 900Mhz Itanim2 cpu (ita102 and ita103)
  • 3 Gbytes memory
  • 36 Gbytes Hard Disk space on /
  • 36 Gbytes Hard Disk space on /scratch (rw for all)
  • 1 Terabytes Hard Disk raid0 space on /raid

Hard Disks

All nodes have 2 internal hard disks :

Network

Several networks interconnect the I-cluster2 :

• 1 Gigabit Ethernet network (default) : One 144 ports Extreme Networks "Aspen 10" switch/router equipment.

  IP adresses : 129.88.98.0/24
  Interface : eth1

• Fast Ethernet network : 5 Fast Ethernet switches (20 nodes per switch), interconnected by 1 Gigabit Ethernet switch.

  IP adresses : 129.88.97.0/24
  Interface : eth0

• Myrinet Network : One 128 ports M3-E128 Myrinet switch.

  IP adresses : 10.1.200.1/24
  Interface : myri0

  Nodes	Interface myri0
  All Nodes	M3F PCI64C-2
  Exceptions
  ita102, ita103, ita104	M3F-PCIXD-2

• 10 Gigabits Ethernet Optical Fiber grid interconnection with GrImage and IdPot clusters : two 10 Gigabits XENPAK-based Ethernet ports on "Aspen 8810" switch/router.

Architecture