Yet another SSD raid question.

[Jaz709]

Hello all, I've been researching ssd's for the past few weeks and made up my mind to go with Intel. Just finished going through 20 pages and cannot find what I'm looking for so I thought I'd ask.

- Will using an X25-M by itself then adding that drive into raid -0 cause a performance loss later ?

Thought I read somewhere that if you're going to run raid with these drives, you should do it form the start. If the drive has been used the system will pick up on that. Sorry if I am not explaining this correctly. Talk about confused.

- Can you suggest a 5.25 ->2.5 bay that'll house 4 drives?

I'd eventually like to end up with 4 drives if all goes well. I am aware that you have to leave a certain percentage free to allow for lack of trim. This will be used with the onboard controller on a GA-EP45-UD3P. Thank you in advance for your help.

 

[sub.mesa]

1) Yes, without reserving space on the SSD, putting it in RAID later means you force the drive to be slow because you don't have TRIM and you did not create a smaller partition. So doing it this way would guarantee low performance.

The proper way to it, would be to reserve space like 10% at the end of the SSD's capacity. That way you will prevent it becoming much slower, especially since in RAID you do not have access to TRIM.

2) Yes, i'm using a 5.25" enclosure that supports four 2,5" drives.

 

[Lateralus]

1) Yes, without reserving space on the SSD, putting it in RAID later means you force the drive to be slow because you don't have TRIM and you did not create a smaller partition. So doing it this way would guarantee low performance.

This would not be a problem if he performed a secure erase on the used drive to clear the mapping tables, and then threw it in a RAID array with another drive, correct? At least that's how I understood the explanation if this in another thread, since a secure erase essentially returns the drive to "new" status (minus write cycles on the cells)...thus a smaller partition could be made at that time and the performance degradation could be avoided?

 

[sub.mesa]

Yes a secure erase resets the drive to factory specs. But if you then use the SSD the 'wrong way' it will get slow again - that's not what you want.

That's why you can force space to be used as reserve pool, by partitioning it. If you don't, you will have to secure erase and reinstall OS every few months; not that appealing at all.

Especially when you're in RAID and unable to use TRIM or the SSD toolbox - you need to reserve space and never use that space. So if the SSDs have been used before; secure-erase them then setup the RAID then make a partition smaller than the full capacity.

If you make one big partition, without reserving space, it might slow down significantly if you write full that partition - OR - you uninstall/reinstall apps frequently. For example, after some months of installing stuff and deleting, your volume is only 25% full - but the SSD thinks its 100% full because those sectors have been written to once; and after that the SSD thinks they are still in use even though you deleted all that stuff. So now your SSD is 25% full but it behaves as if 100% full with low write speeds and half the write endurance. This way you cripple your SSD.