SSD Raid 0 questions

dgingeri

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Anyone out there with experience with RAID 0 and SSDs? Specifically, I'd like to know if anyone has experience with Sandforce SSDs in a RAID 0 format.

I know TRIM isn't transferred to a RAID array, but I'm thinking that won't be an issue. The reason I don't think it will be an issue is that the RAID striping won't generally cross the page lines. it will be writing more than a page at a time per drive, even with the lowest setting. So, if you have a pair of SSDs in a RAID 0 with a 8k stripe, it will be writing 4k per drive at a time, so TRIM and garbage collection won't even be needed. That is assuming the controller lines the stripes up properly. If the controller lines the stripes up wrong, it could seriously degrade performance.

Has anyone set up drives like this, and have you been able to avoid the performance degradation associated with partial page writes? What controller are you using, and how many have you tried? Did you get the performance you were expecting?

I have a feeling this will become more and more common in the near future, and RAID controller manufacturers might actually begin to offer special options for SSD RAIDs.
 

arkoon

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Feb 18, 2011
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18,510



Hi dgingeri

I have been running 2 vertex 2 40GB's in RAID 0 for over 6 months. It is too much for the
ICH9 on my X48 board to utilize. Cold boots are a problem; it just takes a couple/few tries.
Aftermarket BIOS update for iastor are available but do I trust them? No.
On a SATA 2 interface the only payoff for RAID 0 really is the extra storage. I also use Vista 64-bit so couldn't get trim anyway. It has not been a problem, my machine apparently gets enough time idling for GC to work. I transcode lots of Blurays to mkv and
seeing the 300 MB/s working speed is pretty cool.
Summary:
It's fun to play with but real-world increase is not substantial.
 

dgingeri

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I just got my OS installed on them. I'm getting 530MB/s after Windows 7 is installed. (Make sure and install the Intel raid drivers and utility installed, and then enable write caching. The transfer rate increases substantially when this is done.)

Without a partition, I was getting 570MB/s, but once I put a partition on them, the transfer rate reduced a bit. Once I put data on them, it reduced further.

I have noticed that Firefox and Office open almost immediately. This improvement is substantial. I'm really liking it.