Feedback on Block Wear

How Controllers Maximize SSD Life – Feedback on Block Wear

Tempus FugitOne way that SSD controllers maximize the life of an SSD is to use feedback on the life of flash blocks to determine how wear has impacted them.  Although this used to be very uncommon, it is now being incorporated into a number of controllers.

Here’s what this is all about: Everybody knows that endurance specifications tell how much life there is in a block, right?  For SLC it is typically 100,000 erase/write cycles, and for MLC it can be as high as 10,000 cycles (for older processes) but goes down to 5,000 or even 3,000 for newer processes.  TLC endurance can be in the hundreds of cycles.  Now the question is: “What happens after that?”

In most cases individual bits start to 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