Occasional drops in performance monitoring

Occassionally the cnMeastro server stops logging and displaying performance stats for all devices in the network. We have had to reboot the VM to get it back working again. When this happens the devices are all showing as up but the performance graphs are not being populated with data points. It is not happening frequently, but it does happen every two to three weeks and a reboot of the VM seems to be the only way to get things back up and running again. It affects all monitored devices - we have a mix of PMP450 and ePMP onboarded. Possibly this is a known isse but I though I should report it here anyway. We are using cnMaestro on premises at Version 1.3.0-r7