CSC’s new CrayXT4 supercomputer open for use on April 2nd

27.03.2007

CSC’s new Cray XT4 supercomputer (network ID louhi.csc.fi) will be taken into customer use at the beginning of April. The installation was preceded by more than a month of system testing.

Louhi is intended for heavy-duty computing jobs that can be parallelized to a large number of processors. Under normal circumstances, parallel jobs can be run with a minimum of 64 and maximum of 512 computing cores. If specifically requested, jobs larger than this can be accepted, even ones consuming the equipment’s total capacity, if a rationale exists for solving large computational challenges.

Applications for user accounts

Since the beginning of March, users have been able to apply for user accounts. The accounts will be opened when CSC takes Louhi into customer use. User accounts will be granted only for customers, whose program runs will become sufficiently faster by using Louhi. Hence, all customers interested in using Louhi should perform a scalability test for applications that they mean to run on Louhi.

Customers with a valid user account for another CSC computing server (IBMSC, Sepeli or Corona), may request a Louhi test user account by sending an email to usermgr at csc.fi. New customers should apply for their user accounts for Louhi by submitting a user account application, available from our www-pages. The procedure for the pdf-form is: print it, fill it in and mail it to CSC. The application form is different for academic researchers (at universities and polytechnics), and for research institutes and private companies.

Program scalability must be tested

Instructions on how to run scalability tests and present results are available at section Services for researchers.

For more detailed information on scalability testing, contact rinnakkaislaskenta at csc.fi. The users of Louhi can apply for final additional resources, in excess of 10,000 computing units, after an individual computing project account has been opened. The application form for additional resources is available on the website. Applicants are required to evaluate their project needs in computing units for the subsequent 3-6 months.

Reaching the peak level of performance in Europe

The Cray XT4 equipment will be installed in two phases by 2008. The first phase installation comprises 1012 computing nodes, each equipped with a double-core AMD Opteron processor with a clock frequency of 2.6 GHz. The memory capacity is 1GB per a core.

For in-house software development the system contains various compilers, such as Portland, GNU Compiler Collection and PathScale Fortran, C and C++ compilers, MPI, ACML and LibSci libraries, as well as TotalView debugger and Cray’s profiling tools. Louhi uses the PBS Pro batch run system.

At the first phase Louhi’s peak efficiency will be 10.5 Tflops. The final assembly will produce 70 Tflops efficiency, which will make Louhi one of the most efficient supercomputers in Europe.

Additional information:

• New user accounts for Louhi
• Customers with a valid user account for another CSC’s computing server may request a Louhi test user account by sending an email to usermgr at csc.fi.
• Instructions on how to run scalability tests
• For more detailed information on scalability testing, contact rinnakkaislaskenta at csc.fi.
  
• Louhi User's Guide