For the last 3 decades of computer storage use, we’ve operated essentially blindfolded. What we’ve known about performance has been gleaned from artificial benchmarks such as IOMeter and guestimates of IOPS requirements during operations that depend on a sense of how fast an application is running.
The result is something like steering a car without a speedometer ... it’s a mess of close calls and inefficient operations.
On the whole, though, we muddled through. That’s no longer adequate in the storage New Age. Storage performance is stellar in comparison to those early days, with SSDs changing the level of IOPS per drive by a factor of as much as 1000X. Wait, you say, tons of IOPS…why do we have problems?
The issue is that we share much of our data across clusters of systems, while the IO demand of any given server has jumped up in response to virtualization, containers and the horsepower of the latest CPUs. In fact, that huge jump in data moving around between nodes makes driving blind impossible even for small virtualized clusters, never mind scaled-out clouds.
All of this is happening against a background of application-based resilience. System uptime is no longer measured in how long a server runs. The key measurement is how long an app runs properly. Orchestrated virtual systems recover from server failures quite quickly. The app is restarted on another instance in a different server.
