The Tri-Lab Linux Capacity Cluster (TLCC)—Unifying Computing across the NNSA Defense Complex

NNSA's new capacity computing systems, the Tri-lab Linux Capacity Cluster 2 (TLCC2), are NNSA's second joint procurement of this type of supercomputer to replace those procured in 2007. An aggregate total computing capability of three petaFLOP/s (quadrillion floating operations per second) for $39 million comprised the initial delivery.

Capacity computing systems are designed to run a large number of jobs simultaneously on a single system. In the past, each lab conducted its own capacity computing procurements and ran its own software stack machines. With different hardware, operating systems, and tools, these systems provided very different and challenging environments to users, making collaborations difficult and increasing overall costs.

This tri-lab procurement model reduces costs through economies of scale based on standardized hardware and software environments at the three labs—allowing NNSA's more powerful supercomputers to be dedicated to the largest and most complex calculations critical to stockpile stewardship (see Sequoia).

Computing clusters built of "scalable units" (SUs) were delivered to Livermore, Los Alamos, and Sandia labs between September 2011 and June 2012. Each SU represents 50 teraFLOP/s of computing power. These SUs are designed to be connected, much like Legos, to create more powerful systems. Advances in computational technology, enabled in part by NNSA's computing initiatives, have brought down the cost of HPC systems from approximately $100,000,000 per teraFLOP/s in 1995 to less than $17,000 per teraFLOP/s today, a factor of nearly 6000.

TLCC2 clusters support NNSA's Life Extension Program and investigations into technical issues related to aging weapons systems, efforts critical to ensuring the safety, security, and reliability of the nuclear weapons in the stockpile as they age well beyond their intended deployment life.

Lawrence Livermore's TLCC2 clusters, whose names are inspired by the Livermore area wine country, include:

• Zin: 18 SUs, 970 teraFLOP/s peak
• Cab: 8 SUs, 431 teraFLOP/s peak
• Merl: 1 SU, 54 teraFLOP/s peak