How do I clean up R memory without restarting my PC?

user_1533742 0
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I am running my code in R (under Windows) which involves a lot of in-memory data. I tried to use rm(list=ls()) to clean up memory, but seems the memory is still occupied and I cannot rerun my code. I tried to close the R and restart R again, but it is the same, seems memory is still occupied as when I run the codes it says it can't allocate memory (but it could at the first time). The memory seems only cleaned up after I restart my PC.

Is there any way to clean up the memory so that I can rerun my code without restarting my PC every time?

r
8 Answers

Just adding this for reference in case anybody needs to restart and immediatly run a command.

I'm using this approach just to clear RAM from the system. Make sure you have deleted all objects no longer required. Maybe gc() can also help before hand. But nothing will clear RAM better as restarting the R session.

library(rstudioapi)
restartSession(command = "print('x')")
user_48442600

There is only so much you can do with rm() and gc(). As suggested by Gavin Simpson, even if you free the actual memory in R, Windows often won't reclaim it until you close R or it is needed because all the apparent Windows memory fills up.

This usually isn't a problem. However, if you are running large loops this can sometimes lead to fragmented memory in the long term, such that even if you free the memory and restart R - the fragmented memory may prevent you allocating large chunks of memory. Especially if other applications were allocated fragmented memory while you were running R. rm() and gc() may delay the inevitable, but more RAM is better.

user_117300040

I've found it helpful to go into my "tmp" folder and delete all hanging rsession files. This usually frees any memory that seems to be "stuck".

user_74362220
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