Sysadmins are aware of an issue causing file access times to be slow. The issue was first reported on September 17, 2016. As a result, workstations and servers will lock up and cause massive lag times between user input and expected output.
We are still currently evaluation solutions and are working towards a fix.
If you are using a workstation, we suggest to try to use the acmguest account for now, while we work through this issue. The acmguest account is not reliant on accessing personal files, so lag times shouldn't be an issue.
We apologize for the inconvenience. If you have any questions, comments, and/or concerns, please feel free to contact the sigsysadmin mailing list.
Update (September 28, 2016): Sysadmins may have found the issue. It appears to be a switch malfunction. All systems seem to be nominal at this point. We will continue to monitor the situation and report on any additional issues that may have occurred.
ACM/LUG Systems Administrator