2 Fold SSD Raid Question

[hennessy1]

I have an x58 motherboard with just Sata II and 3 Patriot Inferno 240GB ssds. My first question is it worth losing TRIM for putting those in a Raid 0? Will the lifespan and performance take a hit with out that? I am unsure how good the garbage collection on those drives are with the Sandforce 1200 controller.

My second question is will having 3 of those in Raid 0 be bottlenecked by the Sata II controller? If so would it be better to just do 2 in Raid 0 or just completely stick with one?

 

[deimos3428]

I've run three 60GB in RAID0 for the last four months, and if my performance is degrading due to lack of TRIM..well, I sure can't tell. Runs great.

That said, I don't think it's really worth doing unless you've got a lot of data to transfer on a regular basis. I wanted to try it out, but if I were to do it again probably I'd just get a single SSD.

 

[hennessy1]

Do you run into a limitation with speed on the sata II you have those connected too as well?

I also plan on having atleast 100GB of data written to it so would that mess up the performance and I'd be better off with more space?

 

[deimos3428]

Maybe. Frankly I don't know or care if it's limited in any way -- I'm getting just shy of 700 MB/s reads, 600 MB/s writes in Atto and that's more than good enough for my needs.

 

[hennessy1]

So that performance is constant even without trim and just leaving it idle for gc?

 

[deimos3428]

It's without TRIM, but I can't say for sure if it's constant. It'll depend on how heavily you crush the disk, I suppose. I haven't noticed any degradation whatsoever.

 

[hennessy1]

Would a secure erase restore the performance that is lost with the absence of TRIM?

 

[groberts101]

I SE/reimage to bypass throttling every 5-6 weeks depending on the amount of incompressible data written to my array and would think you could go WAY beyond that with 700GB's of capacity. I can go quite a bit longer than that with "typical usage" but I rip vids and do a lot of gfx work on this machine so most users could do far better until the drives "settled in". I assume you understand how Sandforce controllers Durawrite throttling process works?

To keep the array working at unthrottled speeds for a longer time all you need do is allow extra unallocated space(called manual OP,.. I use 80 gigs of 280 available) and allow soem logged off idle time after heavier data sets(incompressible data in particular).

That system would scream with those 3 drives in R0. Mine cannot be bogged down no matter how hard I try.

And also keep in mind that Trim does NOT restore speed on Sandforce drives unless they are completely throttled to the lowest possible state(called a "hammerred state") and is more about lifespan as those dirty blocks are put back into the reserve pool and therefore allowed to be rotated more efficiently. GC has the final say and trim just marks the blocks so it's more efficient at it's job. Throttling is built in and ONLY an SE can release it.

 

[hennessy1]

So would manual OP be the same as not completely filling those drives in raid 0? So without trim in the raid does that severly decrease the life of the drive since it has less known available pool of nand or is that negated by leaving the computer idle for gc to work?

 

[groberts101]

Manual OP will eliminate the baby-sitting/translational loss that occurs from just allocating all space logically. This increases the reserve pool for the controllers to store pre-cleaned blocks and will increase stamina and recovery. Much of my personal testing and advice has been carried through for many users to pool from now on the OCZ forum. Here's a good long read to help understand Sandforce's inner workings.
http://www.ocztechnologyforum.com/f...ives-TRIM-OP-area-use-and-Life-write-throttle

and the available pool is not negated in any manner and just to make sure the remark above settles in a bit more I'll quote myself to avoid the reread... "trim is more about lifespan as those dirty "trim marked blocks" are put back into the reserve pool and therefore allowed to be rotated more efficiently which can have some benefit to those particular nand cells. Ultimately, GC has the final say though as it's the one finishing the job."

In a nutshell, GC on Sandforce's last gen(1xxx series controllers) is known to be on the slow side compared to others. Logoff idles simply allow additional low resource usage/drive activity to promote its efficient use.

 

[hennessy1]

Thank you for your help in having a novice understand. What I have come to the conclusion is to raid the drives and be done with it as I probably will never see the degredation in performance before replacing the drive. Does SE reset all the nand cell so the ones in OP get rotated or does it just use the same cells?

Would this be worth it to do for my raid?
http://www.ocztechnologyforum.com/f...-A-simple-guide-for-speeding-up-EOL-OCZ-SSD-s