Henrik Alsing Friberg
2012-Jan-30 08:04 UTC
[Rd] Deprecation of "--min-nsize" and "--min-vsize"
Hi R-devel, I only run the released version of R where "--min-nsize" and "--min-vsize" have now been deprecated, and am told that this functionality has been removed in the dev-version. However, having R not repeatedly ask the operating system for more memory while executing, and raising the "gc trigger" level so that garbage collection is postproned, is a time-wise effective way of running R scripts. Of course, you need a system that can handle the larger memory footprint. Here is an example: ---------------------------------------------- gc(); system.time({ N = 2000000; SUBLENGTH <- rep(3, N); CONEVAL <- matrix(1:(3*N), ncol=3); cones <- matrix(list(), nrow=2, ncol=N, dimnames=list(c("type","sub"),c())); for (i in 1:N) { cones[,i] <- list("MSK_CT_QUAD", CONEVAL[i,]); } }) gc(); ---------------------------------------------- Normal execution: user system elapsed 28.030 0.190 28.238 With high values of "--min-nsize" and "--min-vsize": user system elapsed 10.330 1.130 11.464 So the effect is a factor 2 to 3. I agree that these arguments are too technical for the average user and that you would rarely really need them, but it would be nice to have an easy way of speeding up R scripts. Also, setting high values of "--min-nsize" and "--min-vsize" gives more consistent system.time() results when more methods are tested after each other, because garbage collection and the availability of memory in the R process does not interfere. Take this as a thought, and not a need-to-have from my side.. Kind regards, Henrik