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bravenewmac
Jul 31, 2013, 04:49 PM
So i just got a new 2013 MBA with 8 GB Ram and the i5 haswell.
So i just ran the geekbench test and got a score of 5814 thats mouch less than in reviews of the same model (example: http://www.primatelabs.com/blog/2013/06/macbook-air-benchmarks/)

also my SSD speed is 320 Mbit write and 729 read. While read seems finde write seems low?

Whats going on ? Did i get a faulty unit or whats up?

thank you guys



APedro
Jul 31, 2013, 05:51 PM
Thats normal since the score u see on geekbench is the best score that some1 got. The ssd score should be a bit higher on write, something like 400 more or less.

jedolley
Jul 31, 2013, 05:55 PM
Do you have an 11"? I think it was determined early on (correct me if I am wrong) that the 11" 128GB SSD (maybe other capacities as well?) were slower than the SSDs on the 13" for whatever reason (maybe manufacturer?).

SteveJobs2.0
Jul 31, 2013, 07:10 PM
I have a 128 gb 13" with Samsung sd and a 256gb 13@ with Samsung. 128gb read is around 700 and write is 400. 256gb one is around 700 for both read and write

TheMythTheMan
Jul 31, 2013, 07:57 PM
128gb hard drives will have the 700/400 read/write, 256 and 512gb will have 700/700... screen size doesn't matter.

OP are you using the 64-bit or free 32-bit version. You have to run the 64-bit version to get those +6000 scores with the i5.

AXs
Jul 31, 2013, 09:06 PM
screen size doesn't 'matter' but is relevant, because for the 11" model people are getting sandisk SSD. Even for 256, and it is not showing the same speed as a samsung SSD.

kage207
Jul 31, 2013, 09:38 PM
128gb hard drives will have the 700/400 read/write, 256 and 512gb will have 700/700... screen size doesn't matter.

OP are you using the 64-bit or free 32-bit version. You have to run the 64-bit version to get those +6000 scores with the i5.
Which gives the 200 point difference.

Jefe's MacAir
Jul 31, 2013, 09:47 PM
screen size doesn't 'matter' but is relevant, because for the 11" model people are getting sandisk SSD. Even for 256, and it is not showing the same speed as a samsung SSD.

I have a Sandisk in my Ultimate and I'm getting 700+ read and write.

cedwhatev
Jul 31, 2013, 10:32 PM
I get around 720/560 read/write, and I have an 11"/i5/8GB/256GB SSD (Sandisk)

AXs
Aug 1, 2013, 02:14 AM
I have a Sandisk in my Ultimate and I'm getting 700+ read and write.

Oh wow I didn't realise Apple put Sandisk in their 512 machines as well.

1BadMac
Aug 1, 2013, 06:31 AM
128gb hard drives will have the 700/400 read/write, 256 and 512gb will have 700/700... screen size doesn't matter.

OP are you using the 64-bit or free 32-bit version. You have to run the 64-bit version to get those +6000 scores with the i5.

This.

128 will always show "artificially" lower due to less NAND on the actual device. It will write just as fast as the 256 drive, it just won't reflect that in the benchmarks because there isn't enough NAND to simultaneously saturate.

Enjoy your MBA and stop worrying about benchmarks.

bravenewmac
Aug 1, 2013, 06:47 AM
ok i ran the geekbench in 32-bit this explains that.

But with the SSD - i have a 128 GB version and a SanDisk SSD.

So the read speed is strange because even if preformed more often i canīt get over 318 MB/s

is this ok??

edit:


This.

128 will always show "artificially" lower due to less NAND on the actual device. It will write just as fast as the 256 drive, it just won't reflect that in the benchmarks because there isn't enough NAND to simultaneously saturate.

Enjoy your MBA and stop worrying about benchmarks.

oh so you are saying the speed is the same?

What is NAND?

Also another question for everyone - how much read/write cycles does a SSD have nowadays?

Weaselboy
Aug 1, 2013, 11:10 AM
But with the SSD - i have a 128 GB version and a SanDisk SSD.

That is your issue right there. Your speeds are normal for the 128GB. Those faster speeds you are seeing in reviews are for the 256GB SSD version and it tests about twice as fast in write speeds.

What is NAND?

It is a type of memory chip used in SSDs that retains data even with no power.

Also another question for everyone - how much read/write cycles does a SSD have nowadays?

Your SSD uses MLC type NAND chips rated for 5,000 write cycles. See info below from this article (http://www.anandtech.com/show/6459/samsung-ssd-840-testing-the-endurance-of-tlc-nand). Even if you write 10GB of data to the SSD every day, it will last 35 years.

Just use it and enjoy it... no reason to worry about wearing out your SSD.

http://imgur.com/SeqlUMF.png

bravenewmac
Aug 1, 2013, 11:20 AM
23 years - ha - thats ok ;)

thankyou a lot guys you helped making me enjoy the mac even more <3

jdechko
Aug 1, 2013, 11:42 AM
Just to further explain the whole write speed on the SSD, here's a quick analogy.

Say you have a very large container of marbles, and you have 4 pipes running to 4 smaller buckets. The pipes can only dispense 100 marbles per minute, maximum, so you can only put 400 marbles per minute, maximum, into the bucket.

Now take the same large container of marbles and run 8 pipes to 8 buckets. The pipe can still only dispense 100 marbles per minute, max, but now the entire system can dispense up to 800 marbles per minute.

If we look at the SSD in these terms, the 128GB models have fewer "buckets" to write to, so the speeds are slower than the 256GB models which have more "buckets"

mayuka
Aug 1, 2013, 12:14 PM
Even if you write 10GB of data to the SSD every day, it will last 35 years.

Only if your hard drive has more than 33% free space left, you have enabled TRIM and you format it from time to time. Otherwise it could be significantly lower.

128gb hard drives will have the 700/400 read/write, 256 and 512gb will have 700/700...

Not if you have FileVault (disk encryption) activated. Write speeds will be approx. halfed. This could explain many slower write speeds.

Weaselboy
Aug 1, 2013, 12:28 PM
Only if your hard drive has more than 33% free space left, you have enabled TRIM and you format it from time to time. Otherwise it could be significantly lower.

SSDs have built in over provisioning, to there is no need to worry about it getting full impacting lifespan.

There is absolutely no need to format an SSD to ensure lifespan.

Not if you have FileVault (disk encryption) activated. Write speeds will be approx. halfed. This could explain many slower write speeds.

Not even close. More like 20-30%. Here (http://www.anandtech.com/show/4485/back-to-the-mac-os-x-107-lion-review/18) is a test.

mayuka
Aug 1, 2013, 12:56 PM
There is absolutely no need to format an SSD to ensure lifespan.

overprovisioning is only about 8 GB on a 128 GB drive, on Samsung drives even less. Everything depend on the implementation. There are better ones and worse. Most new drives do not really need TRIM anymore. With older drives, a low-level format can do wonders. See this article: http://arstechnica.com/information-technology/2012/06/inside-the-ssd-revolution-how-solid-state-disks-really-work/ It really depends on which manufacturer and with chipset you have.

Not even close. More like 20-30%.

The test was done on a Samsung drive as far as I know. Drives from Sandisk and Toshiba (Sandforce based) show higher decreases, about 50%. Also the test was done on SATA II... My 2013 MBA has a Sandisk drive and shows approx. 420 MB/s sequential write speeds with FileVault activated and without approx. 780 MB/s.

Weaselboy
Aug 1, 2013, 01:22 PM
overprovisioning is only about 8 GB on a 128 GB drive, on Samsung drives even less. Everything depend on the implementation. There are better ones and worse. Most new drives do not really need TRIM anymore. With older drives, a low-level format can do wonders. See this article: http://arstechnica.com/information-technology/2012/06/inside-the-ssd-revolution-how-solid-state-disks-really-work/ It really depends on which manufacturer and with chipset you have.

I'm not sure what your point is. OP has a 2013 MBA with an SSD that has native TRIM. That SSD uses MLC NAND chips and the stats I quoted are accurate for OP's application.

I don't see anything in that article or anywhere else that claims reformatting an SSD is in any way helpful for maintaining NAND lifespan. If anything, it would to some small degree reduce lifespan as it would require writing all the drive's data back to the drive after the format.

The test was done on a Samsung drive as far as I know. Drives from Sandisk and Toshiba (Sandforce based) show higher decreases, about 50%. Also the test was done on SATA II... My 2013 MBA has a Sandisk drive and shows approx. 420 MB/s sequential write speeds with FileVault activated and without approx. 780 MB/s.

Again, the OP has a 2013 MBA and none of the 2013 MBA flash storage units use Sandforce controllers, so I don't understand your point. Enabling Filevault on a 2013 MBA will result in about a 20-30% write speed reduction in synthetic tests.

During normal usage with and without Filevault the difference is imperceptible. I know this because I own the exact machine the OP has.

bravenewmac
Aug 1, 2013, 02:36 PM
Weaselboy you sir are awesome

jdechko
Aug 1, 2013, 04:01 PM
Not if you have FileVault (disk encryption) activated. Write speeds will be approx. halfed. This could explain many slower write speeds.

Not even close. More like 20-30%. Here (http://www.anandtech.com/show/4485/back-to-the-mac-os-x-107-lion-review/18) is a test.

I think that was only on the Toshiba Drives used in previous models. My 2013 Air 128GB has a SanDisk drive, and with FileVault Enabled, I get the 700/400.

Weaselboy
Aug 1, 2013, 04:11 PM
I think that was only on the Toshiba Drives used in previous models. My 2013 Air 128GB has a SanDisk drive, and with FileVault Enabled, I get the 700/400.

Correct... those used a Sandforce controller.

johnjey
Aug 1, 2013, 05:36 PM
So i just got a new 2013 MBA with 8 GB Ram and the i5 haswell.
So i just ran the geekbench test and got a score of 5814 thats mouch less than in reviews of the same model (example: http://www.primatelabs.com/blog/2013/06/macbook-air-benchmarks/)

also my SSD speed is 320 Mbit write and 729 read. While read seems finde write seems low?

Whats going on ? Did i get a faulty unit or whats up?

thank you guys

Sorry but seems faulty as i reported 730+ speeds earlier on this forum in one of the posts

Hungry&Foolish
Aug 1, 2013, 05:47 PM
Weaselboy you sir are awesome

I think that as well. Great guy.

kodeman53
Aug 1, 2013, 05:52 PM
Only if your hard drive has more than 33% free space left, you have enabled TRIM and you format it from time to time. Otherwise it could be significantly lower.

Yeah, like only 20 years. :rolleyes:

mayuka
Aug 2, 2013, 02:11 AM
I'm not sure what your point is.

My point is that you can't generalize the behaviour of a Samsung SSD over to Toshiba or Sandisk. The latter have quite different implementation on the inside. It's not just Sandforce, there are differences between Sandforce implementations too, which is practically always neglected. And it's not about the NANDs, it's about the chipset. Low-level reformatting does not increase the lifespan of every NAND, of course, but it increases the health of the drive as the access table is being re-shuffled again, a known problem with some brands because the implemtation was known to produce inconsitent access states over time. Theory does not always work as expected. That's exactly what the linked article is saying. We'll meet again in a few years.