Add support for querying per-process disk and network stats
Submitted by Robert Roth
More and more requests come in for per-process disk IO or network IO monitoring. I'm not sure how this can be implemented in a cross-platform way, /proc/PID/net/netstat contains the network IO details (at least I see two numbers occasionally changing, one must be the upload, the other the download, but not detailed in man proc), and /proc/PID/io (since kernel 2.6.20). Having methods to query these for the processes with the processlist would be nice to have.