Hi Jay and Benilton, Thank you both for your help. When I do not use the dimnames argument, everything works fine:
x <- big.matrix(nrow=2e4,ncol=5e5,type='short',init=0) #18 Gb RAM used rm(x) #18 Gb RAM used gc() #no RAM used However, when I use dimnames, I get this problem, reproducibly: x <- big.matrix(nrow=2e4,ncol=5e5,type='short',init=0,dimnames=list(2e4,5e5)) #18 Gb RAM used rm(x) #18 Gb RAM used gc() #18 Gb RAM used I looked in /dev/shm throughout this and saw nothing there. Might these files be stored elsewhere? In any event, I have an easy work-around now, so this isn't a big deal, but is it a bug in bigmemory that it doesn't return RAM when the dimnames argument is used? Here's my sessioninfo > sessionInfo() R version 2.10.1 (2009-12-14) x86_64-pc-linux-gnu locale: [1] C attached base packages: [1] graphics grDevices datasets utils stats methods base other attached packages: [1] doMC_1.2.0 multicore_0.1-3 foreach_1.3.0 codetools_0.2-2 iterators_1.0.3 pnmath0_0.0-2 On Sat, Feb 6, 2010 at 2:44 PM, Jay Emerson <jayemer...@gmail.com> wrote: > >>>> See inline for responses. But people are always welcome to contact >>>> us directly. > > Hi all, > > I'm on a Linux server with 48Gb RAM. I did the following: > > x <- > big.matrix(nrow=20000,ncol=500000,type='short',init=0,dimnames=list(1:20000,1:500000)) > #Gets around the 2^31 issue - yeah! > >>>> We strongly discourage use of dimnames. > > in Unix, when I hit the "top" command, I see R is taking up about 18Gb > RAM, even though the object x is 0 bytes in R. That's fine: that's how > bigmemory is supposed to work I guess. My question is how do I return > that RAM to the system once I don't want to use x any more? E.g., > > rm(x) > > then "top" in Unix, I expect that my RAM footprint is back ~0, but it > remains at 18Gb. How do I return RAM to the system? > >>>> It can take a while for the OS to free up memory, even after a gc(). >>>> But it's available for re-use; if you want to be really sure, have a >>>> look >>>> in /dev/shm to make sure the shared memory segments have been >>>> deleted. > > Thanks, > > Matt > > -- > John W. Emerson (Jay) > Associate Professor of Statistics > Department of Statistics > Yale University > http://www.stat.yale.edu/~jay > -- Matthew C Keller Asst. Professor of Psychology University of Colorado at Boulder www.matthewckeller.com ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.