You can find the ipython log file in the DSS administration screen, under Maintenance > Log files > ipython.log. Alternatively, if you have access to the server by command line, the file is located in <DSS_DATA_DIR>/run/ipython.log.
Having said that, it is a bit surprising to get a memory crash on a 1GB csv file. Assuming you use pandas to load and transform it, a good rule of thumb is to have 5-10GB of free memory (see http://wesmckinney.com/blog/apache-arrow-pandas-internals/). Have you checked that you are not printing too much to the notebook output? [EDIT] Sorry, I had read too quickly and did not notice that you were using R. Could you check what is the object.size of the CSV file after it is loaded into an R object?
Are you at liberty to share your code and underlying data?