Title
On Optimizing the Arithmetic Precision of MCMC Algorithms
Abstract
Markov Chain Monte Carlo (MCMC) is an ubiquitous stochastic method, used to draw random samples from arbitrary probability distributions, such as the ones encountered in Bayesian inference. MCMC often requires forbiddingly long runtimes to give a representative sample in problems with high dimensions and large-scale data. Field-Programmable Gate Arrays (FPGAs) have proven to be a suitable platform for MCMC acceleration due to their ability to support massive parallelism. This paper introduces an automated method, which minimizes the floating point precision of the most computationally intensive part of an FPGA-mapped MCMC sampler, while keeping the precision-related bias in the output within a user-specified tolerance. The method is based on an efficient bias estimator, proposed here, which is able to estimate the bias in the output with only few random samples. The optimization process involves FPGA pre-runs, which estimate the bias and choose the optimized precision. This precision is then used to reconfigure the FPGA for the final, long MCMC run, allowing for higher sampling throughputs. The process requires no user intervention. The method is tested on two Bayesian inference case studies: Mixture models and neural network regression. The achieved speedups over double-precision FPGA designs were 3.5x-5x (including the optimization overhead). Comparisons with a sequential CPU and a GPGPU showed speedups of 223x-446x and 16x-18x respectively.
Year
DOI
Venue
2013
10.1109/FCCM.2013.31
FCCM
Keywords
Field
DocType
Markov processes,Monte Carlo methods,belief networks,field programmable gate arrays,floating point arithmetic,inference mechanisms,logic design,neural nets,optimisation,regression analysis,sampling methods,statistical distributions,Bayesian inference,FPGA-mapped MCMC sampler,GPGPU,MCMC acceleration,MCMC algorithms,Markov chain Monte Carlo method,arbitrary probability distributions,arithmetic precision optimization,automated method,double-precision FPGA designs,field programmable gate arrays,floating point precision,large-scale data,mixture models,neural network regression,optimization process,precision-related bias,random samples,sampling throughputs,sequential CPU,ubiquitous stochastic method,user-specified tolerance,FPGA,Markov Chain Monte Carlo,Monte Carlo simulation,arithmetic precision
Monte Carlo method,Markov process,Bayesian inference,Markov chain Monte Carlo,Computer science,Floating point,Algorithm,Probability distribution,Mixture model,Estimator
Conference
Citations 
PageRank 
References 
5
0.47
9
Authors
3
Name
Order
Citations
PageRank
Grigorios Mingas1514.80
Farhan Rahman250.47
Christos Savvas Bouganis340049.04