Patent ID: 8176367

Claim:
A solid state drive, the solid state drive comprising: a first number of memory portions each including a plurality of flash memory cells, wherein a second number of the first number of memory portions are addressable, and wherein a difference between the first number and the second number is an over provisioned number of memory portions; a control circuit, wherein the controller circuit includes: an unreliable block identification circuit, wherein the unreliable block identification circuit is operable to determine that one or more of the first number of memory portions is unreliable, and wherein upon determining that one or more of the first number of memory portions is unreliable the over provisioned number of memory portions is reduced; and a partial failure indication circuit, wherein the partial failure indication circuit is operable to disallow write access to any of the memory portions upon determination that the over provisioned number of memory portions is less than or equal to a threshold level; a time stamp circuit, wherein the time stamp circuit is operable to identify a first point in time when the partial failure indication circuit disallowed write access to the memory portions; and an end of life indication circuit, wherein the end of life indication circuit is operable to estimate a second point in time when the ability to read one or more of the plurality of memory portions can no longer be guaranteed by adding a fixed time increment to the point in time, wherein the fixed time increment is a predefined estimate of how long data will remain readable in the memory cells after the first point in time.