UK National HPC Service

Computer Services for Academic Research Logo
Home | Helpdesk | Machine Status | Search | Apply

Wren (Origin 300)

The SGI Origin 300 system has been named Wren in honour of the English mathematician Christopher Wren (1793-1841).


This system has 16 MIPS processors, each running at 500 MHz. This machine is intended to act as an interactive front-end to the other Origin systems as well as for compilations and manipulating data on the storage area network (SAN). The only facility for batch submission to Wren is that provided for single processor compilation jobs which need longer time limits than might be possible for interactive sessions.

Image of Wren & SAN


Aspect of the system Details
Processors 16 x 500 MHz MIPS R14000 processors
Memory 16 GBytes memory
Cache hierarchy Each processor has 2MB Level 2 cache, 32 KB Level 1 data cache, 32 KB Level 1 instruction 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 IRIX
Partitioning This machine is a 16 processor single system image (SSI)
Maximum job size Wren is intended to be an interactive front end to the other Origin machines and there is no facility for large scale batch work on this system
Theoretical peak performance 16 Gigaflops - 16 processors x theoretical peak of 1 Gigaflop
Host Address

Configuration Information

Wren is configured with 4 processors set aside for operating system tasks, 10 processors set aside for interactive access and 2 available for long compilation jobs which need to be submitted through the batch system to overcome the CPU time limit imposed on interactive sessions.

Wren is visible to the outside world as and X applications can be run directly from an ssh session provided that X forwarding is turned on at your local machine.

Wren acts as the primary Metadata server for the storage area network (SAN) and should be used for small jobs and tasks which have to access a large number of files such as compilations and heavy use of the tar command.

Page maintained by This page last updated: Monday, 23-Aug-2004 11:38:56 BST