9 Search Results

Extending the Binomial Checkpointing Technique for Resilience
In terms of computing time, adjoint methods offer a very attractive alternative to compute gradient information, re quired, e.g., for optimization purposes. However, together with this very favorable temporal complexity result comes a memory requirement that is in essence proportional with the operation count of the underlying function, e.g., if algo rithmic differentiation is used to provide the adjoints. For this reason, checkpointing approaches in many variants have become popular. This paper analyzes an extension of the socalled binomial approach to cover also possible failures of the computing systems. Such a measure of precaution is of special interest for massivemore » 
Covering Resilience: A Recent Development for Binomial Checkpointing
In terms of computing time, adjoint methods offer a very attractive alternative to compute gradient information, required, e.g., for optimization purposes. However, together with this very favorable temporal complexity result comes a memory requirement that is in essence proportional with the operation count of the underlying function, e.g., if algorithmic differentiation is used to provide the adjoints. For this reason, checkpointing approaches in many variants have become popular. This paper analyzes an extension of the socalled binomial approach to cover also possible failures of the computing systems. Such a measure of precaution is of special interest for massive parallel simulationsmore » 
Calculating Reuse Distance from Source Code
The efficient use of a system is of paramount importance in highperformance computing. Applications need to be engineered for future systems even before the architecture of such a system is clearly known. Static performance analysis that generates performance bounds is one way to approach the task of understanding application behavior. Performance bounds provide an upper limit on the performance of an application on a given architecture. Predicting cache hierarchy behavior and accesses to main memory is a requirement for accurate performance bounds. This work presents our static reuse distance algorithm to generate reuse distance histograms. We then use these histogramsmore » 
An optimized treatment for algorithmic differentiation of an important glaciological fixedpoint problem
We apply an optimized method to the adjoint generation of a timeevolving land ice model through algorithmic differentiation (AD). The optimization involves a special treatment of the fixedpoint iteration required to solve the nonlinear stress balance, which differs from a straightforward application of AD software, and leads to smaller memory requirements and in some cases shorter computation times of the adjoint. The optimization is done via implementation of the algorithm of Christianson (1994) for reverse accumulation of fixedpoint problems, with the AD tool OpenAD. For test problems, the optimized adjoint is shown to have far lower memory requirements, potentially enablingmore »Cited by 2
All Records
Creator / Author
"Narayanan, Sri Hari Krishna"
Resource Type
Availability
Creator / Author
Research Organization