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View Full Version : Rev B Air Question: How much does nearly full SSD impair performance/trigger fan?




ghileman
Jan 14, 2011, 01:28 AM
I've got a 2+ year old Rev B with 128GB SSD with only 4GB of space left.

Fan comes on a lot and stays on, even when vents aren't blocked and when not watching video.

Can't say for sure but it seems like snappiness has dropped a bit too as I've started to run out of SSD space.

Thanks.



Hellhammer
Jan 14, 2011, 12:28 PM
Having that little free space will definitely impact the performance. I suggest you to read this (http://www.anandtech.com/show/2738/8), it explains SSD degradation in layman terms. I would try to have at least 10GB of free space, preferably more.

rawdawg
Jan 14, 2011, 12:41 PM
Good article Hellhammer.

I recently bought a OWC 60GB SSD for my MBP. I was under the impression the OWC SDDs don't have this problem? Am I correct and why? Or is it just marketing?

Based on the article, would it be advisable to every so often clone your SSD to another drive, format the SSD, and then clone it back? Wouldn't that "reset" the issue with the degradation?

Hellhammer
Jan 14, 2011, 01:01 PM
Good article Hellhammer.

I recently bought a OWC 60GB SSD for my MBP. I was under the impression the OWC SDDs don't have this problem? Am I correct and why? Or is it just marketing?

Based on the article, would it be advisable to every so often clone your SSD to another drive, format the SSD, and then clone it back? Wouldn't that "reset" the issue with the degradation?

OWC SSDs, just like all SandForce based SSDs have built-in TRIM which means the actual block will be erased instead of just left there. I suggest you to read this (http://www.anandtech.com/show/2738/10) as it again, explains TRIM in layman terms. OWC drives also ship with quite a lot extra space which is for garbage collection so that helps too.

What I've seen, OWC drives don't suffer from degradation so you don't have to do anything. Of course, it's still advised to have some free space there so it will operate smoother.

Kilamite
Jan 14, 2011, 01:31 PM
Based on the article, would it be advisable to every so often clone your SSD to another drive, format the SSD, and then clone it back? Wouldn't that "reset" the issue with the degradation?

No, because it'll fill all the pages in a block, because they are fully writable again. Rather than being in a state where they are there, but allowed to be overwritten. If that makes sense.. I know what I'm trying to say!

Hellhammer
Jan 14, 2011, 01:36 PM
No, because it'll fill all the pages in a block, because they are fully writable again. Rather than being in a state where they are there, but allowed to be overwritten. If that makes sense.. I know what I'm trying to say!

There are tools which will perform a "secure erase" which will clear all blocks. Basically that should make the drive like new. However, like I said, that is not needed with SSDs like OWC

rawdawg
Jan 14, 2011, 01:44 PM
I've reached the limit in my understanding but thanks for that additional article and relieving my concern since I bought an OWC SSD. It sounds like TRIM ought to be the only way to go with SSDs. The article did mention there are still issues with rewrites (files that aren't deleted first) but I'm assuming it's not that big an issue. Just glad I went with the OWC one (as I've heard suggested here before).

I would be interested in hearing Kilamite's explanation again as to why cloning it back onto a formated SSD wouldn't work. Are you saying all that would do is clone it back with the exact same problem? Then again, sounds like I don't have to worry about it.

thanks

ghileman
Jan 14, 2011, 05:32 PM
thank you for the responses