Over Provisioning

How Controllers Maximize SSD Life – Over Provisioning

Tempus FugitOver provisioning is one of the most common ways that SSD designers can help assure that an SSD has a longer life than the flash’s endurance rating would support.  If an SSD contains more flash than is presented at its interface, the controller can manage wear across a larger number of blocks while at the same time accelerating disk performance by moving slow operations like block erases out of the way of the SSD’s key functions.

Many people like to compare wear leveling to rotating a car’s tires.  In this vein, think of over provisioning as having a bunch of spare Continue reading

How Controllers Maximize SSD Life

Tempus FugitHow do controllers maximize the life of an SSD?  After all, MLC flash has a lifetime of only 10,000 erase/write cycles or fewer and that is a very small number compared to the write traffic an SSD is expected to see in a high-workload environment, especially in the enterprise.  Still, MLC is becoming the norm in the enterprise.

How do they do that?

This is where SSD architects really earn their pay.  There are eight basic techniques that The SSD Guy knows of to extend SSD life beyond Continue reading