A recent SeachStorage blog by Phil Goodwin, When Using SSD is a Bad Idea, offers some interesting advice on when and where you should avoid using solid state drive (SSD) solutions in the data center. I felt some of these tips could use some serious insight and elaboration so here goes.
Tip1: Don’t Use SSD when applications are not read intensive? Goodwin backs up this tip with the assertions that SSD write performance is poor and SSD wear is accelerated by lots of writes. He then cites a 90/10 read/write ratio as an arbitrary ideal for an SSD candidate.
First of all, I would argue that memory cell wear is really a function of average write IOPS, not simply whether an application is write heavy or not. To cite an extreme example, an application whose work is 100 percent writes is clearly not a good fit for SSD based on the Tip 1. However, SSD will last many years if this write-heavy application averages 100 writes per second. If it averages 10,000 write IOPS, your SSD will wear out 100 times faster.