I've been running into an issue recently where Rstudio has been very slow to respond when asked to autocomplete the name of a file stored on a mapped network drive.
This is reproduced reliably by asking Rstudio to autocomplete a file name or a directory, then asking it to perform any other function. I can ask the autocomplete to complete a file name in the script editor and then simply press in the console window and Rstudio will hang for several minutes.
When I press ctrl+backtick (ctrl+`) "get_completions" appears to be the major culprit, though at other times, "check_for_external_edit" appears to take a long time as well. I'm not sure on how inter-dependent these functions are, so I can't necessarily split the problem between the two of these.
Using R through the windows terminal (Rterm) rather than Rstudio, autocomplete is instant in the same network location, however there have been other isolated problems reported with access times on the network drive.
This problem has started recently on a drive which was previously working perfectly and does not occur when autocompleting a non-network drive from the same machine. The only change which might contribute is an increase in the size of the network drive (an NFS share from my institution), which suggests some kind of issue with indexing large network drives may be at play, although I cannot pin point the exact start time of the problem with the time the size of the network drive was increased.
Similar issues in the community appear to me to be connected to this:
Running Windows 10 - 64