We have quite a few physical machines in our environment, yet we have no trending data over a period of time for disk latency statistics. We can easily run the standard iostat commands to see what the latency is at any particular point in time. But there is no historical data that we can pull from easily.
Are there any recommended tools to monitor disk latency other than screen scraping the output of iostat in a script? We have IOPs graphs, but those are generally not overly useful unless we have latency statistics paired with them.
We have MRTG available currently for trending, and can use Nagios for alerting of a particular threshold being exceeded.
We're generally using RHEL systems on Dell platforms. So if there are any specific easy-to-use tools provided by these providers that I'm unaware of, pointing those out would be beneficial as well.