[Crib-list] SPEAKER: Gene Cooperman [Computational Research in Boston Seminar -- Friday, September 5, 2008]

[Shirley Entzminger]

 		COMPUTATIONAL RESEARCH in BOSTON SEMINAR


DATE:		FRIDAY, SEPTEMBER 5, 2008
TIME:		12:30 PM
LOCATION:	Building 32, Room 144  (Stata Center)

Pizza and beverages will be provided by 12:15 PM.


Title:		DISK BASED PARELLEL COMPUTATION AND CHECKPOINT RESTART

Speaker:	GENE COOPERMAN  (Northeastern University)


ABSTRACT:

This talk represents some joint work of the speaker's High Performance 
Computing Laboratory.  It highlights two loosely related topics.  First, a 
vision for disk-based parallel computation is presented, based on our 
catch phrase "Disk is the New RAM".  As the number of CPU cores grows, the 
RAM per CPU core tends to diminish on commodity computers.  The solution 
is to use the many local disks of a computer cluster.  Such a solution has 
been used to find a lower bound on solutions to Rubik's cube, among other 
applications.

Fifty local disks have approximately the bandwidth of a _single_ RAM 
subsystem.  Thus, 50 local disks of a cluster have the potential to 
emulate a single 50 terabyte RAM subsystem.  The obvious fallacy is the 
issue of disk latency.  The solution is a new run-time library with an 
abstraction for many data structures and access methods.  The library 
hides the awkward low-level plumbing of the data parallelism.  Appropriate 
language design principles (simpler language constructs are more efficient 
than complex constructs) then bias the end user application toward good 
latency tolerance.

The second part of this talk then describes a mature user-space 
checkpoint-restart system, DMTCP, that transparently supports distributed, 
multi-threaded applications.  Naturally, DMTCP is fully sufficient to 
checkpoint and restart our disk-based applications.

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Massachusetts Institute of Technology
Department of Mathematics
Cambridge, MA  02139



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