Sure. Here's some additional insight regarding your questions. First, currently using 1.5GB of memory. Happy to increase if that might be an issue.
Second, in terms of what I mean by unusable. I've had two situations in the last week where I was unable to use the project for several hours. Here's a quick summary of both situations:
"The previous R session was abnormally terminated due to an unexpected crash. You may have lost workspace data as a result of this crash".
Six days ago, I was working in this project and started getting the error above. I tried Terminating R, Restarting R, Closing and Reopening the browser and no matter what I did, I would continue to get this error. The following morning the project was back to normal.
Read Only File System Pop-Up
The second issue, unrelated to the first but with similar consequences, is the item referred to in this post. When I would open the project, I would get a pop-up that said "Read Only File System". Then the project would open as normal with two exceptions. First, I couldn't use write_csv, write_rds, etc. to write data to a file. I would either get an error that the system could not create the connection or that the specified directory did not exist (although it did). Please note that internet connection was fine as I was able to read data and run scripts. Second, the "git" tab was missing entirely from IDE.
Again, I tried repeatedly to restart, terminate, etc. and nothing worked. After a few hours, project returned to normal behavior.
Hope that helps and if you have any advice, please let me know. In both cases, all functionality returned to normal but that's obviously not a long term solution for me. If there's something I need to be doing differently, will be happy to change process.