Does the advent of flash devices constitute a radical change for
secondary storage? How should database systems adapt to this
new form of secondary storage? Before we can answer these
questions, we need to fully understand the performance
characteristics of flash devices. More specifically, we want to
establish what kind of IOs should be favored (or avoided) when
designing algorithms and architectures for flash-based systems. In
this paper, we focus on flash IO patterns, that capture relevant
distribution of IOs in time and space, and our goal is to quantify
their performance. We define uFLIP, a benchmark for measuring
the response time of flash IO patterns. We also present a
benchmarking methodology which takes into account the particular
characteristics of flash devices. Finally, we present the results
obtained by measuring eleven flash devices, and derive a set of
design hints that should drive the development of flash-based
systems on current devices.