Dear all: I try a package called "rparallel", and it can make your multiple cores desktop PC have parallel computation. The following are my code: ######################## library(rparallel) msd <- function(x)c(mean(x),sd(x)) m <- matrix(rnorm(100000*100),ncol=100) st <- Sys.time() M <- NULL if( "rparallel" %in% names( getLoadedDLLs()) ) { runParallel( resultVar="M", resultOp="rbind",nWorkers=2) }else { for(i in 1:100000){ M <- rbind(M, msd(m[i,])) } } Sys.time() - st ######################## I know I can do the same thing by "apply". but just want to try the package. and I got the following error message, ######################## ...running parallel version LCOM::read ERROR - No length read from pipe [\\.\pipe\worker0] LCOM::receiveRequest ERROR - Reading Request Type from pipe [\\.\pipe\worker0] LWM::manageWorker ERROR - Calling receiveRequest(). For worker: 0 ######################## Does anyone have idea what happen? My OS is windows XP sp3, and my cpu is Intel Pentium D 820 2.80GHz. Thanks for every reply ¡×¡×¡×¡×¡×¡×¡×¡×¡×¡×¡×¡×¡×¡×¡×¡× Oscar Chang ±i©v·¢ Research Assistant Division of Biostatistics and Bioinformatics National Health Research Institutes (NHRI) Tel : 886-37-246-166 ext. 36116 email : wwfc@nhri.org.tw [[alternative HTML version deleted]]