Displaying 2 results from an estimated 2 matches for "1265230".
2010 Dec 23
1
speed issues? read R_inferno by Patrick Burns: & a memory query
...ts.
2. is the modest decrease in memory consumed by new method expected? (having
read R_Inferno I was, perhaps naively, expecting more of an improvement)
? or am I missing something (more than likely! )
Thanks
M
> gc()
used (Mb) gc trigger (Mb) max used (Mb)
Ncells 786300 21.0 1265230 33.8 1166886 31.2
Vcells 948412 7.3 3244126 24.8 3766604 28.8
> cat("old version")
Virtual size before call: 881692
user system elapsed
131.872 14.417 159.653
Virtual size after call: 899404
> 899404-881692
[1] 17712
##################
> gc()
used (M...
2012 Mar 04
1
hash table clean-up
...3 21.9
Vcells 247949 1.9 786432 6.0 641735 4.9
>
> for (i in 1:100000) {
+ name <- paste("x", runif(1), sep="")
+ assign(name, NULL)
+ rm(list=name)
+ rm(name)
}
>
> gc()
used (Mb) gc trigger (Mb) max used (Mb)
Ncells 831714 22.3 1368491 36.6 1265230 33.8
Vcells 680551 5.2 1300721 10.0 969572 7.4
It appears the increase in memory usage is due to the way R's
environment hash table operates
(http://cran.r-project.org/doc/manuals/R-ints.html#Hash-table): as
objects with new names are created, new entries are made in the hash
table; but...