TRIM for SSD in Raid 0

chinesepanda

Distinguished
Jul 14, 2009
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0
18,530
I recently got two Kingston SSDs and put them in RAID 0 but now I've been lurking around the internet and I find this heated debate as to whether or not SSD's with TRIM do not support TRIM while in RAID 0

One side of the argument is:
TRIM rearranges and identifies which files are able to deleted but it doesn't work because RAID 0 splits and separates the data making it unidentifiable. Intel themselves have recognized this problem and released firmware to counter it.

Other side is:
If you're running Windows 7 then your operating natively TRIMs any storage drive running at 0 RPM.

I was just looking for clarification since I have two SSDs and while both support TRIM and I am running Windows 7, they are in RAID 0 so I'm not sure what to do about TRIM. If it doesn't support TRIM, is there a program that I can use to simulate it?
 
Solution
The problem is that once you put the drives into a raid array, the OS and even most of the hardware in your system only see one drive, that is really an emulation layer on top of two drives. Trim commands can be produced, but the raid controller has no clue what to do with them. The SSD's only have data written to them, but in raid 0, the whole file may not be on one drive. The files get stripped across the drives so that several write operations can occur at once. Since that data isn't associated at a specific point on a drive there's no way to trim that space when the file is erased.

Some very smart people are working on this, its a thorn in the side of the SSD world right now. It'll probably take intel making a chipset that can...

someone19

Distinguished
Jan 16, 2011
441
3
18,810
The problem is that once you put the drives into a raid array, the OS and even most of the hardware in your system only see one drive, that is really an emulation layer on top of two drives. Trim commands can be produced, but the raid controller has no clue what to do with them. The SSD's only have data written to them, but in raid 0, the whole file may not be on one drive. The files get stripped across the drives so that several write operations can occur at once. Since that data isn't associated at a specific point on a drive there's no way to trim that space when the file is erased.

Some very smart people are working on this, its a thorn in the side of the SSD world right now. It'll probably take intel making a chipset that can recognize if an array contains a SSD, and a way for trim commands to be parsed correctly to operate in a sane manner.
 
Solution