In the preceding chapters, we’ve done everything we possibly could to avoid disk IO. By optimizing our database design and tuning queries, we minimized the workload demand and consequently reduced the logical IO demand on MongoDB. Optimizing memory reduced the amount of that workload that translated into disk activity. If you’ve applied the practices in the previous chapters, then your physical disk demand has been minimized: now it’s time to optimize the disk subsystem to meet that demand.
Reducing IO demand should ...
