Air SSD Lifespan?

Check out http://en.wikipedia.org/wiki/Solid-state_drive

"SSD that are based on FLASH memory, have only a limited number of write / erase cycles. For uses that see a lot of writes,their life span is far shorter than traditional HDDs that are magnetic based. Although SSD's have built in techniques to minimize the write/erase cycles, it is expected that the application or the Operating System take the initiative to make them last longer. Besides claims of years of life, there are no accurate numbers on their true lifespan. The lifespan will vary widely, depending upon how the SSD is used."

John,

Here's some rough math for you. My SSD has a MTBF (Mean Time Before Failure) of 2,000,000 hours.

24 hours in a day x 365 days in a year = 8,760 hours. That goes into 2 million approximately 228 times (years). Now mind you a component's MTBF is not a "hard and fast" rule, manufacturers don't actually run them for 228 years to verify this, it's an average expected life span before the device fails or becomes unusable.

In other words, they'll last a while. I've been using SSDs for coming up on 5 years and some of our original drives still work to this day.

AFAIK, TRIM support should not really affect the lifespan of the drive, but rather the permormance. When a file is deleted from a normal HDD, the pointer in the allocation table is simply deleted, and new data can just be written over the old. However, flash doesn't work this way - the actual data on the chip must be erased before new data is written (no overwrites). TRIM addresses this.

What WILL extend the life of a drive is wear-leveling. A flash-aware controller or filesystem will spread out the data being written evenly so no one cluster of flash chips are used more than others. This is only useful for SSDs because there are no seek times. Whether HFS+ supports this I do not know off the top of my head.

Jack

Got MacBook Air Mid 2011 with Smasung SSD. Do I need to use some tricks as spotlight turn off, etc in order to increase the lifespan of SSD?

Thanks.

deleted by user

It isn't necessary to disable to Spotlight or any other core OS X services to improve the life of the SSD. My first generation MacBook Air (SSD) is on its 5th owner (handed down across family members) and it works like a charm, heck it's on its 3rd party and still the original hard drive.

I really wouldn't worry about it, there's been no evidence (online or otherwise) that I've been able to find of users with normal use burning out the acceptable life span of an SSD within the first 3-4 years of ownership. Excluding technical manufacturing failures, of course.

Mine failed today. Mid 2011 Macbook Air. 256 GB flash memory, i7, the whole 9. Crapped out in 16 months with light usage. Mostly writing school papers.Worst thing about having this happen today? I can't retrieve my files. I've been on the phone with apple all day. The only option I have left is to replace the hard drive. and it's not covered underwarranty.Worst possible timing too it fails 1 week before the semester ends and less than 24 hours before most of my final projects are due. To go from a 4.0 GPA to anything less in the last week of pre-med simply because I believed the "ssd" hype.

That's all it is. Yes they are faster. But out of all the PCs I've own I've never had a HD fail this fast and in this way, just going from working find to no access and no way to recover my files.

Texed wrote:

just going from working find to no access and no way to recover my files.

Well hopefully as a graduation present you can buy an external hard drive to backup all your data or sign-up for anyone of the many free, cloud storage services that can also serve as a backup.

"Is there a tool for OS X that allows the measurement of the SSD Lifespan?"

Although not OS X specific, you can use a regular calander.

As Jason I use SSD's for 5 years now, and all are working fine. If you have the factory installed SSD the OS will use a Trim command to clean up the SSD for writes to come. I use non-Apple SSD's so I install the Trim command after replacing the HDD with a SSD.

Trim makes the writes go faster than when you do not use Trim (or Garbage Collection), it will also lengthen the life of the SSD, but it also makes backing-up even more necessary ( because recovery of erased data will almost be impossible).

Texed wrote:

But out of all the PCs I've own I've never had a HD fail this fast and in this way, just going from working find to no access and no way to recover my files.

All hard drives fail, SSD and mechanical - end of story. Working in the biz I've seen drives die within days of the computer's purchase, within months, a couple days out of warranty, and even 10 year old drives still going strong. Your drive's failure after 16 months says nothing about an SSDs longevity. Now if over the next year we start hearing about lots of SSDs dying or if an SSD manufacturer extends its warranty protection that will mean something. Until then all we know is that a) you didn't buy AppleCare, b) you didn't have a backup, c) you aren't happy. Had you a & b not been true, c would be less true.

That's not what MBTF means at all.

Imagine you have 10 hard drives that have an expected service life of 5 years each.

Let's say 2 of them die before 5 years, and 1 dies after 5 years, and the other 7 are fine.

You have 50 years of service life. 2 total failures that occured within the service life the hard drives. You have 25 years MTBF. That does not mean the average HD lasts 25 years.