library(foreach)
library(snow)
library(doSNOW)

cl <- makeCluster(2, type="SOCK")
registerDoSNOW(cl)
m <- matrix(rnorm(9), 3, 3)
foreach(i=1:nrow(m), .combine=rbind) %dopar%  (m[i,] / mean(m[i,]))
stopCluster(cl)