Good Paper by Laura M. Grupp, John D. Davis and Steven Swanson (thank you)
In recent years, flash-based SSDs have grown enor- mously both in capacity and popularity. In high- performance enterprise storage applications, accelerating adoption of SSDs is predicated on the ability of manufacturers to deliver performance that far exceeds disks while closing the gap in cost per gigabyte. However, while flash density continues to improve, other metrics such as a reliability, endurance, and performance are all declining. As a result, building larger-capacity flash- based SSDs that are reliable enough to be useful in enterprise settings and high-performance enough to justify their cost will become challenging.
Read on here