I am doing large DB imports on a Postgres instance running in a Proxmox 1.9 OpenVZ virtualized Ubuntu 11.04. For some reason, the executable that initiates and controls the import (or Postgres), always stops at some point, typically, when there is high I/O load on the system (i.e. the proxmox host or in any of the VM instances) caused in addition to that of the importing process. I am trying to figure out the root issue and whether I can potentially avoid it. Ps tells me that wchan = n_tty_ for the importing process (which is sleeping). First of all what does this mean and what are good practices in how to debug further?