I think this is the best answer. To those who flamed OP for being 'stupid' or 'ignorant', probably you, yourself, are being 'stupid' or 'ignorant'. Apple is using 10-base in storage calculation now, so the only plausible explanation is the fact that SSD formatting does take some space so it would reduce usable space to users.
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Anyone annoyed by SSD being smaller than advertised?
- Thread starter JodyK
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I think this is the best answer. To those who flamed OP for being 'stupid' or 'ignorant', probably you, yourself, are being 'stupid' or 'ignorant'. Apple is using 10-base in storage calculation now, so the only plausible explanation is the fact that SSD formatting does take some space so it would reduce usable space to users.
Seriously, all the people bashing the OP have no clue. This isn't the GiB to GB conversion, you are getting less space. Have you guys even bothered to look at your partition ?
In GiB :
$ df -h /
Filesystem Size Used Avail Capacity Mounted on
/dev/disk0s2 113Gi 68Gi 44Gi 61% /
In GB :
$ df -H /
Filesystem Size Used Avail Capacity Mounted on
/dev/disk0s2 121G 73G 48G 61% /
So the drive is not a 128GB drive, it's a 121 GB drive, at least according to the partition. If we look at the disk, the partition is made using the entire sector count, give or take 1, which doesn't amount to 7 GB :
$ sudo fdisk /dev/disk0
Password:
Disk: /dev/disk0 geometry: 14751/255/63 [236978176 sectors]
Signature: 0xAA55
Starting Ending
#: id cyl hd sec - cyl hd sec [ start - size]
------------------------------------------------------------------------
1: EE 1023 254 63 - 1023 254 63 [ 1 - 236978175] <Unknown ID>
2: 00 0 0 0 - 0 0 0 [ 0 - 0] unused
3: 00 0 0 0 - 0 0 0 [ 0 - 0] unused
4: 00 0 0 0 - 0 0 0 [ 0 - 0] unused
Finally, system profiler reports the drive as a 121 GB drive :
APPLE SSD TS128C:
Capacity: 121.33 GB (121,332,826,112 bytes)
Model: APPLE SSD TS128C
So everyone bashing the OP : you guys are wrong, he is right.
The advertised capacity of the computer should what is shown in the "Get Info" pane of the drive, that's the number we see when we use our computers, it's the only one that means anything to us. All the so-called justifications that people are coming up with that are to do with different ways of counting the capacity are just BS.
Normal people just want to know what they've got usable, and that they're not getting ripped off, they don't want to know that the seller is really clever and counts a different way from the rest of us. Eggs are eggs, if you buy six in a box, there shouldn't be five because the farmer counts in hexabloodydecimal or whatever. As to "doing research before you buy", what a load of crud, it says 64GB on the box, that's what should be in it.
Normal people just want to know what they've got usable, and that they're not getting ripped off, they don't want to know that the seller is really clever and counts a different way from the rest of us. Eggs are eggs, if you buy six in a box, there shouldn't be five because the farmer counts in hexabloodydecimal or whatever. As to "doing research before you buy", what a load of crud, it says 64GB on the box, that's what should be in it.
So, the OP was right. He still doesn't have any more space on his SSD. I suggest he send his MBA back to Apple.
One can only assume Apple is using that ~5,5% as Spare Area.
Spare area is used mainly for three purposes: 1) read-modify-writes, 2) wear leveling and 3) bad block replacement.
Which is quite important to keep the performance of the drive at an acceptable level over a longer period.
That doesn't change the fact that Apple should clearly have advertised the 128GB drive as a 120GB drive.
We do know for a fact that the 128GB Solid State Drive from Toshiba uses 4 x 32GB flash modules.
Spare area is used mainly for three purposes: 1) read-modify-writes, 2) wear leveling and 3) bad block replacement.
Which is quite important to keep the performance of the drive at an acceptable level over a longer period.
That doesn't change the fact that Apple should clearly have advertised the 128GB drive as a 120GB drive.
We do know for a fact that the 128GB Solid State Drive from Toshiba uses 4 x 32GB flash modules.
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Before the forums were in maintenance yesterday I also found it was likely due to over-provisioning. The drive is of the advertised capacity it just keeps a certain part of it to keep itself in tip top shape. I found a thread on MR about it too in the mba section. I dont really want to look for it again.
Before the forums were in maintenance yesterday I also found it was likely due to over-provisioning. The drive is of the advertised capacity it just keeps a certain part of it to keep itself in tip top shape. I found a thread on MR about it too in the mba section. I dont really want to look for it again.
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People.
SSD drives are different from Hard-drives. They have 'wear leveling' technology which a small section of the memory is reserved to extend life when a data sector fails to read/write at the physical level. Think of it as having and LCD monitor that repairs itself when there is a dead pixel. Of course, it wont repair forever, but that would take several writes to consume all of the reserved sectors. In this case, a 128GB SSD has a reserve of 7GB worth of data tiles(sectors) that replace the broken ones.
So 121GB is the actual raw usable data at the system level. Also memory chip is measured in powers of 2 not powers of 10. Snow Leopard now calculates drives as power of 10 so SSD capacities are affected by this.
A bare NAND chip's size is physically correct as stated by the manufacturer. As soon as you attach a NAND controller, a feature is turned on that will take part of the sectors for reserve. So I wouldn't blame the manufacturer.
As for Apple, it would be better if they just advertise storage space according how the system reads it. (60GB, 120GB, 250GB etc.)
SSD drives are different from Hard-drives. They have 'wear leveling' technology which a small section of the memory is reserved to extend life when a data sector fails to read/write at the physical level. Think of it as having and LCD monitor that repairs itself when there is a dead pixel. Of course, it wont repair forever, but that would take several writes to consume all of the reserved sectors. In this case, a 128GB SSD has a reserve of 7GB worth of data tiles(sectors) that replace the broken ones.
So 121GB is the actual raw usable data at the system level. Also memory chip is measured in powers of 2 not powers of 10. Snow Leopard now calculates drives as power of 10 so SSD capacities are affected by this.
A bare NAND chip's size is physically correct as stated by the manufacturer. As soon as you attach a NAND controller, a feature is turned on that will take part of the sectors for reserve. So I wouldn't blame the manufacturer.
As for Apple, it would be better if they just advertise storage space according how the system reads it. (60GB, 120GB, 250GB etc.)
Not everyone. My OCZ drive gives me pretty much what it states on the housing and packaging. YMMV.
That missing space is
a) formatting (not much taken up)
and
b) the OS Image that allows the really fast waking, IIRC that's about 4GB
No. Others that have stated it is for wear-leveling are right. It's not for the OS image because the drive doesn't present this extra space to the OS at all. See my post.
Don't make stuff up, if you don't know, don't try to post speculation when all has been detailed already. It makes you look like all the guys on page 1 that bashed the OP saying he was wrong because of the GiB to GB factor when it clearly hasn't been an issue since Snow Leopard.
Now this is even worse than those who said the OP is wrong. At least they had arguments, even if they were wrong. This is just blatant ignorance.
yeah, i understand the OP's frustration, basically apple should advertise it as 60GB, 120GB etc.
Then again, do you really care about a few GB's? After all, it is to keep your SSD performing at it's best.
Then again, do you really care about a few GB's? After all, it is to keep your SSD performing at it's best.
I doubt anyone is returning their MBA in light of this. Pointing out something is one thing, I don't think the OP was majorly pissed. He did use "annoyed" in the title not "anger that rival's that of the gods!".
People like MikePA just can't see the world as grey. Everything needs to be black and white. If it's not white, it's black. Hence his comment that went a bit overboard.
I don't need you to, nor want you to speak for me. Yes, only an elitist can see the finer shades of gray when it comes to computing space on an SSD. Pedantry at its finest.
Then why did you suggest the OP's only recourse was to return his MBA ? You know, you can be annoyed by a feature of a product, but still overall be happy with it. Shades of grey and all...
At least do apologize for your out of place comment.
To the people who are flaming the OP, have any of your realized why SSDs in Macs don't show obvious signs of degradation even when Mac OS X doesn't support TRIM? Chew on that for a bit.
This kinda reminds me of the threads back in the day where people would ask why their 250GB HDD was showing up as less. After numerous posts explaining the difference between 10^9 and 2^30, someone would always chime in with "it's because of formatting".