SandForce SF-1200 / SF-1500 performance degradation explained (anand)

Joined
Aug 8, 2010
Messages
832
Anand is on top of the SF-1200 performance degradation situation:
http://www.anandtech.com/show/3997/ocz-revodrive-x2-review/4

For the moment, it looks like we can avoid the performance drop by keeping a spare parition filled with compressible data.

SSD controller manufacturers have avoided the TRIM issue by equipping drives with idle garbage collection. The principle behind idle garbage collection is simple. When the SSD controller detects a period of no activity, it can query the file system for available addresses, and then internally mark those addresses for cleaning.

The RevoDrive x2 features idle garbage collection, which for most users should be sufficient to keep the drive running at full speed. There is a problem however. Current SandForce drives have a bug that impacts TRIM (and idle garbage collection). If you fill all available NAND on a SandForce drive by writing incompressible data to all user accessible LBAs and all spare area, the drive will no longer be able to restore itself to full performance via TRIM or any idle garbage collection. This impacts the RevoDrive x2 as well as standard SandForce SSDs.

I'm still in the early stages of measuring the real world impact of this bug and I made SandForce aware of it two weeks ago. At this point I'd simply caution against operating a SandForce drive near capacity filled with primarily incompressible data (e.g. compressed videos, photos). The problem is even more sensitive on a card like the RevoDrive x2 since there's no way to secure erase the drive to fully recover from a reduced performance state.

Expect to hear more about this in the next major SSD article on AnandTech.
 

sub.mesa

2[H]4U
Joined
Feb 16, 2010
Messages
2,508
Interesting article!

But this has to be wrong:

The problem is even more sensitive on a card like the RevoDrive x2 since there's no way to secure erase the drive to fully recover from a reduced performance state.
This should include "on Windows".
 

Computurd

Gawd
Joined
Dec 19, 2008
Messages
956
hmmm seems to be much song and dance for a very expensive drive to work correctly.
 
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