I just ran across this video from Sun Microsystems that demonstrates a source of disk latency that we usually don't think about. It's short and quite amusing. Take a look.
But being the analyst that I am, I also wanted to highlight some of the pieces that make the demonstration possible.
The technology that's under the covers, measuring the disk latency and so forth, is DTrace, a component of Solaris, originally developed by Bryan Cantrill. By way of background, here's what I wrote upon its introduction in Solaris 10:
DTrace stands for "Dynamic Tracing" … Read more