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SSD in Raid 0

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January 13, 2011 8:56:01 PM

I am building rig with SB 2500K and Asus P8P67 PRO.
I am thinking of using 2x64GB SSDs in RAID 0.
is it possible to use SSDs in RAID 0 and will i gain any performance with it?
do i need anything special hardware/software to work this out?
any help in this regard is appreciated.

More about : ssd raid

a c 175 G Storage
January 14, 2011 1:33:32 AM

pcninja said:
I am building rig with SB 2500K and Asus P8P67 PRO.
I am thinking of using 2x64GB SSDs in RAID 0.
is it possible to use SSDs in RAID 0 and will i gain any performance with it?
do i need anything special hardware/software to work this out?
any help in this regard is appreciated.


Yes, it is possible, however, I don't recommend it.

1) With raid-0, you will have to use the Intel raid drivers which do not pass on the "trim" command to the SSD. As the drive gets filled, you will get performance degradation.
2) No, you will not get any performance boost with it. I know, I tried it with two Intel X25-M 80gb drives. Synthetic transfer rates were wonderful. But when I replaced them with a single 160gb drive performance was the same.

I suggest you get a single 128gb drive instead. Larger drives can access more nand chips in parallel(sort of an internal raid-0), and will perform a bit better.
Be certain to specify sata mode as AHCI(not IDE or raid) in the bios. You will then get the windows drivers which will properly pass on the trim command.
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January 21, 2011 1:56:54 AM

geofelt said:
Yes, it is possible, however, I don't recommend it.

1) With raid-0, you will have to use the Intel raid drivers which do not pass on the "trim" command to the SSD. As the drive gets filled, you will get performance degradation.
2) No, you will not get any performance boost with it. I know, I tried it with two Intel X25-M 80gb drives. Synthetic transfer rates were wonderful. But when I replaced them with a single 160gb drive performance was the same.

I suggest you get a single 128gb drive instead. Larger drives can access more nand chips in parallel(sort of an internal raid-0), and will perform a bit better.
Be certain to specify sata mode as AHCI(not IDE or raid) in the bios. You will then get the windows drivers which will properly pass on the trim command.


Thanks Geofelt for your reply.
Regarding the TRIM command, the SSDs i am using do support it in RAID 0 & here is article which suggests Intel's driver support it now
http://guru3d.com/news/intel-brings-trim-to-ssds-in-rai...

also Tom's $2000PC uses same SSDs in RAID 0
http://www.tomshardware.com/reviews/build-a-pc-overcloc...

i appreciate your input on this.
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a c 175 G Storage
January 21, 2011 3:06:28 AM

pcninja said:
Thanks Geofelt for your reply.
Regarding the TRIM command, the SSDs i am using do support it in RAID 0 & here is article which suggests Intel's driver support it now
http://guru3d.com/news/intel-brings-trim-to-ssds-in-rai...

also Tom's $2000PC uses same SSDs in RAID 0
http://www.tomshardware.com/reviews/build-a-pc-overcloc...

i appreciate your input on this.


Interesting, particularly since the article is about a year old.
As best as I can tell, the SSD trim support means that trim will be passed on only to those SSD's attached to the intel controller that are NOT oart of a raid array attached to the controller. So, if you have two SSD's attached in raid-0, you will not get trim passed to them.
Here is a reference that explains it.
http://techreport.com/discussions.x/18653
I think I have read that it is a hardware limitation of raid attachments. Too bad, I was interested.

Regardless, since 90% of what we do is small reads and writes, the value of raid-0 for sequential operations is minimal.
Synthetic benchmarks look wonderful, but that is not what we do.

When I raided two 80gb ssd's, it was the gen1 drives that had their own garbage collection, and did not support trim. I did it to get a single 160gb image for the boot drive, not for performance.
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January 21, 2011 3:33:05 PM

geofelt said:
Interesting, particularly since the article is about a year old.
As best as I can tell, the SSD trim support means that trim will be passed on only to those SSD's attached to the intel controller that are NOT oart of a raid array attached to the controller. So, if you have two SSD's attached in raid-0, you will not get trim passed to them.
Here is a reference that explains it.
http://techreport.com/discussions.x/18653
I think I have read that it is a hardware limitation of raid attachments. Too bad, I was interested.

Regardless, since 90% of what we do is small reads and writes, the value of raid-0 for sequential operations is minimal.
Synthetic benchmarks look wonderful, but that is not what we do.

When I raided two 80gb ssd's, it was the gen1 drives that had their own garbage collection, and did not support trim. I did it to get a single 160gb image for the boot drive, not for performance.


I think you are right it doesnt support TRIM in RAID. Even though some of people in that discussion are saying they confirmed the TRIM in RAID using Winodows trim command.
I am not sure how can Tom recommended that in RAID 0 if no controller support it. WHY??
Too bad i already got the 2x64GB SSDs with very good deal so i have to use both of them.
I dont want to use them as 2 separate disks so probably i will go with RAID 0 & use some cleaner utility.
The SSD garbage collection is it function of controller? how can find out if my SSD supports the garbage collection or not?
do i have any other option to use as single disk?
Thanks Again!!
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a c 175 G Storage
January 21, 2011 3:43:04 PM

How a SSD manages free space is a function of the controller chip, and the microcode that is implemented in that controller. Different SSD's with the same controller chip may perform differently.

What brand and model are the SSD's that you bought?

You will probably do well if you use them in raid-0 to get a single 128gb image.
I would not worry too much about it. You will still benefit from fast random reads which is a large part of what we do.

When the drive gets near full, ot all the free blockes have been used, it will take more time to do writes because a read/rewrite will be involved.
Some vendors will offer stand alone utilities that you can run from time to time to free up blocks the way "trim" does autimatically.
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January 21, 2011 4:13:30 PM

geofelt said:
How a SSD manages free space is a function of the controller chip, and the microcode that is implemented in that controller. Different SSD's with the same controller chip may perform differently.

What brand and model are the SSD's that you bought?

You will probably do well if you use them in raid-0 to get a single 128gb image.
I would not worry too much about it. You will still benefit from fast random reads which is a large part of what we do.

When the drive gets near full, ot all the free blockes have been used, it will take more time to do writes because a read/rewrite will be involved.
Some vendors will offer stand alone utilities that you can run from time to time to free up blocks the way "trim" does autimatically.


i have A-DATA S599 with SandForce SF-1222 Controller

here newegg link
http://www.newegg.com/Product/Product.aspx?Item=N82E168...
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