Intel SRT excessive writes

[Stickmansam]

Hi all,

I've currently got a Adata SP900 64GB running Enhanced Intel SRT on my 2TB drive. I'm using the entire drive as the cache but this thread I saw seems to be I should tone it down to about 45-50GB to get some more over provisioning.

http://forums.anandtech.com/showthread.php?t=2302991

The main concern is that even on a pretty stable usage pattern, the drive seems to rack up about 20-30GB of writes a day. Given the 3k p/e cycle (and 30gb writes) and 10x Write Amplification, I'll get just under two years of usage but I want the drive to last longer than that.
Is getting this amount of writes a day a normal occurance or is the cache thrashing it self? I know Enhanced mode is write through so if I am downloading my steam library, will that show up in SSD writes?

Also, will adding more over provisioning help long term endurance? (Will the cache trash itself more)

 

[JellyRoll]

This is one of the only cases where adding overprovisioning will actually make sense in a desktop environment.

 

[Hellhammer]

10x write amplification sound like an overkill, especially with a SandForce based drive. WA of 1-3x sounds more realistic, which will increase the life your drive significantly. Assuming 30GiB of writes a day and WA of 3x, your drive should last for 5.8 years (though keep in mind that the P/E rating just means the data retention time will be 1-year at the stated amount of P/E cycles - the drive will still continue to work).

Added OP will increase the lifespan as average WA will be lower but SandForce already has very low WA due to real-time compression (can be under 1x) so your drive actually has addition OP thanks to that (host may write 1GB but only 0.9GB gets written for example and the leftover space is used as OP).

 

[johny12]

10x write amplification sound like an overkill, especially with a SandForce based drive. WA of 1-3x sounds more realistic, which will increase the life your drive significantly. Assuming 30GiB of writes a day and WA of 3x, your drive should last for 5.8 years (though keep in mind that the P/E rating just means the data retention time will be 1-year at the stated amount of P/E cycles - the drive will still continue to work).

Added OP will increase the lifespan as average WA will be lower but SandForce already has very low WA due to real-time compression (can be under 1x) so your drive actually has addition OP thanks to that (host may write 1GB but only 0.9GB gets written for example and the leftover space is used as OP).

SandForce has claimed to achieve a typical write amplification of 0.5, with best-case values as low as 0.14 in the SF-2281 controller. OP is part of all SSDs that use Flash memory, Users can easily increase the OP if desired generally higher OP provides Higher write performance,Lower “Write Amplification”with Longer Flash life endurance