BLUE GENE Sunitha M. Jenarius

What is Blue Gene A massively parallel supercomputer using tens of thousands of embedded PowerPC processors supporting a large memory space With standard compilers and message passing environment

Why the name “Blue Gene”? “Blue”: The corporate color of IBM “Gene”: The intended use of the Blue Gene clusters – Computational biology, specifically, protein folding

History Dec’99, IBM Research announced $100M US effort to build a Petaflop scale supercomputer. Two goals of The Blue Gene project : – Massively parallel machine architecture and software – Bio-Molecular Simulation – advance orders of magnitude November 2001, Partnership with Lawrence Livermore National Laboratory (LLNL) and this resulted in …

Results Linpack Top 500 Supercomputers

Blue Gene Projects Four Blue Gene projects : – BlueGene/L – BlueGene/C – BlueGene/P – BlueGene/Q

Blue Gene/L The first computer in the Blue Gene series IBM first announced the Blue Gene/L project, Sept. 29, 2004 Final configuration was launched in October 2005

Blue Gene/L - Unsurpassed Performance Designed to deliver the most performance per kilowatt of power consumed Theoretical peak performance of 360 TFLOPS Final Configuration (Oct. ‘05) scores over 280 TFLOPS sustained on the Linpack benchmark. Nov 14, ‘06, at Supercomputing 2006, Blue Gene/L was awarded the winning prize in all HPC Challenge Classes of awards.

Blue Gene/L Architecture Can be scaled up to 65,536 compute or I/O nodes, with 131,072 processors Each node is a single ASIC with associated DRAM memory chips Each ASIC has MHz IBM PowerPC processors PowerPC processors – Low-frequency, low-power embedded processors, superior to today's high-frequency, high-power microprocessors by a factor of 2 or more

Blue Gene/L Architecture contd… – Double-pipeline-double-precision Floating Point Unit – A cache sub-system with built-in DRAM controller Node CPUs are not cache coherent with one another FPUs and CPUs are designed for low power consumption – Using transistors with low leakage current – Local clock gating – Putting the FPU or CPU/FPU pair to sleep

Blue Gene/L Architecture contd… 1024 nodes System Overview

Blue Gene/L Architecture contd… 1 rack holds 1024 nodes or 2048 processors Nodes optimized for low power consumption ASIC based on System-on-a-chip technology – Large numbers of low-power system-on-a-chip technology allows it to outperform commodity clusters while saving on power – Aggressive packaging of processors, memory and interconnect – Power Efficient & Space Efficient – Allows for latencies and bandwidths that are significantly better than those for nodes typically used in ASC scale supercomputers

Blue Gene/L Networks Each node is attached to 3 main parallel communication networks – 3D Torus network - peer-2-peer between compute nodes – Collective network – collective & global communication – Ethernet network - I/O and management (such as access to any node for configuration, booting and diagnostics )

Blue Gene/L System Software System software supports efficient execution of parallel applications Compiler support for DFPU (C, C++, Fortran) Compute nodes use a minimal operating system called “BlueGene/L compute node kernel” – A lightweight, single-user operating system – Supports execution of a single dual-threaded application compute process – Kernel provides a single and static virtual address space to one running compute process – Because of single-process nature, no context switching required

Blue Gene/L System Software contd… To allow multiple programs to run concurrently – Blue Gene/L system can be partitioned into electronically isolated sets of nodes – The number of nodes in a partition must be a positive integer power of 2 – To run program – reserve this partition – No other program can use till partition is done with current program – With so many nodes, component failures are inevitable. The system is able to electrically isolate faulty hardware to allow the machine to continue to run

Blue Gene/L System Software contd… Parallel Programming model – Message Passing – supported through an implementation of MPI – Only a subset of POSIX calls are supported – Green threads are also used to simulate local concurrency

Blue Gene/C Sister-project to BlueGene/L Renamed to Cyclops64 Massively parallel, supercomputer-on-a-chip cellular architecture Cellular architecture gives the programmer the ability to run large numbers of concurrent threads within a single processor.

Blue Gene/P Architecturally similar to BlueGene/L Expected to operate around one petaflop Expected around 2008

Blue Gene/Q Last known supercomputer in the Blue Gene series Expected to reach 3-10 petaflops

Resources Wikipedia.org IBM website – ( ne.html) ne.html pap207.pdf