Proposal: Partitioning a SDD for "RAID" like benifits?

[bdombro]

I did a search on this subject, and could not find any similar works.

RAIDing partitions doesn't make sense for HDDs, but what about SDDs?

My proposal is this: Since SDDs contain an array of independent memory chips, it is theoretically possible to partition a SDD into two or more sets of chip arrays and RAID the partitions to allow parallel access.

Doing so would offer several of the benefits in performance, reliability and flexibility of RAID within a single SDD!

To top it off, if the end-user could set this, the user could make trade-offs of capacity and speed within a single SDD.

For example: For me Windows rarely exceeds 15GB. If I have a 64GB SDD, I could drastically improve performance by partitioning the memory chips into 4 16GB partitions and raiding them.

 

[jrst]

That's effectively how most (all?) decent SSD's work these days. Internally they use multiple channels in parallel (think RAID-0). The performance you see externally for a single device is as good as it gets for that device; the only way to increase performance is to use multiple devices.

For a good overview of why what, and how, see http://onfi.org/presentations/ (ONFI is the Open NAND Flash Interface organization).

 

[cjl]

It doesn't work that way. You wouldn't speed up the drive at all - if anything you would slow it down. As jrst said, they already effectively do that internally - you would need to RAID several drives to see a performance gain, not just several partitions.

 

[505090]

you cannot well you could but you should not raid a single drive like it will only hurt performance

 

[bdombro]

Hmm yeah it makes sense for them to already incorporate parallel access internally.

And 505090 you are correct given that they already implement a "raid" configuration internally.

Thank guys!