CirrusYeah, we're using Zabbix and it has something called calculated items. You don't necessarily need to know the timestamp but rather the interval you're doing the polling.
Let's say you make one request every 10 seconds and your current total client throughput for the virtual server you're polling is 10kb. 10 seconds later you're polling again and get 20kb.
20kb-10kb=10kb (the VS has had a client throughput of a total 10 kb during these 10 seconds)
To get the average kb per second you then divide this with 10 and get 1kb/second.
Hope that's clearer.
/Patrik
