>> It's certainly possible that the error I was receiving was a different >> reason, though similar symptoms. We started seeing filesystems go >> read-only, and only rebooting would clear it up. > > I use that setting on the "Host OS" for VMWare to prevent a whole vm > from getting killed. > > That setting will maintain a minimum amount of free memory available to > prevent a large program that requests memory quick from depleting all > available memory and causing the program killer from killing the highest > RAM process. > > If you are on a Host OS box, the biggest Memory processes are your VMs, > and getting one killed off because memory reaches zero is not good. > > I don't have any idea how it would fix journal errors on a drive, but I > guess it could. > It's been a few years since I put in the tuning, but here's some info that might be useful: http://communities.vmware.com/thread/20690?start=0&tstart=0 In particular, others had reported seeing this error: "kernel: journal_get_undo_access: No memory for committed data". I don't recall that error in my case, but might explain why the tuning fixed the problem. There's a bugzilla for this: https://bugzilla.redhat.com/show_bug.cgi?id=179605