Thomas Pujol
2007-Dec-14 00:58 UTC
[R] RODBC, optimizing memory, "Error: cannot allocate vector of size 522 Kb".
I am using RODBC and "odbcConnect". I have successfully used odbcConnect to extract "modest" amounts of data from SQL. For convenience, (and maybe speed?) I wish, if possible, to extract larger amounts of data in a single query. (I am running R2.6.0 under a machine running Windows Small Business Server with 3mb of RAM. I run gc() prior to attempting the query. I have attempted to maximize the memory R uses by running the command "memory.size(4095)") After attempting my "odbcConnect" query, I receive the following error message: "Error: cannot allocate vector of size 522 Kb". After I received the message, I obtained the following statistics re my memory use: memory.limit(size = NA)/1000 #reports memory size [1] 4.095> memory.size(max = F)/1000 #reports amount of memory currently in use[1] 1.930705> memory.size(max = T)/1000 #reports maximum amount of memory obtained from the OS[1] 1.93925 Before I give up and go back to running many queries to extract my data, I wanted to ask if there were any suggestions. (I really do wish to extract all this data for local storage as R-files on my hard-drive, it is just a question of the easiest and fastest process.) Thanks. --------------------------------- [[alternative HTML version deleted]]
Prof Brian Ripley
2007-Dec-14 07:04 UTC
[R] RODBC, optimizing memory, "Error: cannot allocate vector of size 522 Kb".
This question is nothing to do with RODBC. You need to study the rw-FAQ Q2.9: I believe you should be able to get up to (almost) 3GB on that system. (BTW, you seem confused about units: I hope you have 3GB of RAM, where G means 1024^3.) On Thu, 13 Dec 2007, Thomas Pujol wrote:> I am using RODBC and "odbcConnect". I have successfully used > odbcConnect to extract "modest" amounts of data from SQL. For > convenience, (and maybe speed?) I wish, if possible, to extract larger > amounts of data in a single query. > > (I am running R2.6.0 under a machine running Windows Small Business > Server with 3mb of RAM. I run gc() prior to attempting the query. I > have attempted to maximize the memory R uses by running the command > "memory.size(4095)") > > After attempting my "odbcConnect" query, I receive the following error message: > "Error: cannot allocate vector of size 522 Kb". > > After I received the message, I obtained the following statistics re my memory use: > memory.limit(size = NA)/1000 #reports memory size > [1] 4.095 >> memory.size(max = F)/1000 #reports amount of memory currently in use > [1] 1.930705 >> memory.size(max = T)/1000 #reports maximum amount of memory obtained from the OS > [1] 1.93925 > > Before I give up and go back to running many queries to extract my data, I wanted to ask if there were any suggestions. (I really do wish to extract all this data for local storage as R-files on my hard-drive, it is just a question of the easiest and fastest process.) Thanks. > > > > > --------------------------------- > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at 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. >-- Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595