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Newton (SGI Altix 3700)

The SGI Altix 3700 machine has been named Newton in honour of the English mathematician Sir Isaac Newton (1643-1727).


The system has 512 Itanium 2 processors, 384 of which have a clock speed of 1.3 GHz and are capable of a peak performance of 5.2 Gigaflops, and 128 of which have a clock speed of 1.5 GHz and are capable of a peak performance of 6 Gigaflops. The system also has a total of 1 Terabyte of memory. The machine uses SGI's NUMAlink interconnect providing very low latency, high bandwidth communication. It is configured as a single system image, with a set of local disks for the operating system and some temporary storage, together with access to the storage area network (SAN). The maximum job size available is 502 processors.

Image of Newton


Aspect of the system Details
Processors 384 x 1.3 GHz and 128 x 1.5 GHz Intel Itanium 2 processors
Memory 1 Terabyte memory
Cache hierarchy Each processor has 256 KB Level 2 cache, 16 KB Level 1 data cache, 16 KB Level 1 instruction cache. The 1.3 GHz processors have 3 MB Level 3 cache, and the 1.5 GHz processors have 6 MB Level 3 cache.
Interconnect SGI NUMAlink providing sub-microsecond hardware latency, 3-5 microseconds MPI latency, sub-microsecond latency for one-sided communications, 6.4GB/s aggregate bandwidth per brick (4 CPUs).
Operating System Linux kernel with SGI Propack extensions (based on Redhat 7.2).
Partitioning The machine is configured as a 512 processor single system image.
Maximum job size 502 processors
Theoretical peak performance 2.7 Teraflops - 384 processors x theoretical peak of 5.2 Gigaflops + 128 processors x theoretical peak of 6 Gigaflops.
Host Address

Configuration Information

Newton is now configured as a 512 processor single system image, running one copy of the Linux operating system, visible to the outside world as This has only recently become possible due to advances in Linux scalability, some of which have involved changes to the open source Linux kernel and some of which have been included in SGI's Propack extensions. Six processors on the system have been set aside for operating system tasks (the boot cpuset) and another four are given over to interactive use (the service cpuset). The remaining 502 processors, 128 at 1.5GHz and 374 at 1.3GHz, should be available for batch work, hence this is the maximum job size of the machine. During core hours, the development queue will take up 16 of the 1.3GHz processors. Therefore since jobs over 358 processors will have to span the two types of processor, they will initially only be run by special request to Users must submit jobs to the newt15 queue (using the -q newt15 option to bsub) in order to run on the 1.5GHz processors. No job will run across both 1.3 GHz and 1.5GHz processors unless it is too large to be run without doing so.

Note that X applications such as totalview can be used by jobs in the development queue provided the DISPLAY environment variable is set correctly in your batch script and you have allowed access to your local machine (i.e. your local firewall allows incoming X traffic and you have used the xhost command to give access permissions to newton). It is also possible to run X applications from your interactive ssh session provided that X forwarding is turned on at your local machine.

Further Newton local configuration information is provided as follows:

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