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Ommid
Jan 21, 2011, 06:28 PM
Hi all

I added an SSD to my Mac Pro today and ran XBench, having run it now on my Air the figures seem shockingly bad!! Is there any way to improve this??

Results 64.77
System Info
Xbench Version 1.3
System Version 10.6.6 (10J567)
Physical RAM 2048 MB
Model MacBookAir2,1
Drive Type APPLE SSD SM128
Disk Test 64.77
Sequential 47.69
Uncached Write 25.43 15.61 MB/sec [4K blocks]
Uncached Write 61.11 34.58 MB/sec [256K blocks]
Uncached Read 45.33 13.26 MB/sec [4K blocks]
Uncached Read 163.30 82.08 MB/sec [256K blocks]
Random 100.92
Uncached Write 47.30 5.01 MB/sec [4K blocks]
Uncached Write 64.80 20.74 MB/sec [256K blocks]
Uncached Read 1398.42 9.91 MB/sec [4K blocks]
Uncached Read 426.44 79.13 MB/sec [256K blocks]



MultiFinder17
Jan 21, 2011, 08:15 PM
Those do seem a bit awful - my 2009 Air with an OWC SSD got:


System Info
Xbench Version 1.3
System Version 10.6.6 (10J567)
Physical RAM 2048 MB
Model MacBookAir2,1
Drive Type OWC Mercury Extreme Pro SSD
Disk Test 217.78
Sequential 128.97
Uncached Write 184.61 113.35 MB/sec [4K blocks]
Uncached Write 183.71 103.94 MB/sec [256K blocks]
Uncached Read 59.20 17.33 MB/sec [4K blocks]
Uncached Read 306.39 153.99 MB/sec [256K blocks]
Random 699.51
Uncached Write 1029.75 109.01 MB/sec [4K blocks]
Uncached Write 334.88 107.21 MB/sec [256K blocks]
Uncached Read 1827.92 12.95 MB/sec [4K blocks]
Uncached Read 823.79 152.86 MB/sec [256K blocks]

What did your Pro get to make you notice? Also, numbers aren't everything - does it feel slower than your Pro?

Ommid
Jan 22, 2011, 05:15 AM
It feels like it has got progressively slower which I know is a problem

The Pro is getting like 200 on every test bar the one which is a bit lower at around 50. This is the 2008 Air with the standard Apple SSD

Thiol
Jan 22, 2011, 05:47 AM
Hi all

I added an SSD to my Mac Pro today and ran XBench, having run it now on my Air the figures seem shockingly bad!! Is there any way to improve this??

Results 64.77
System Info
Xbench Version 1.3
System Version 10.6.6 (10J567)
Physical RAM 2048 MB
Model MacBookAir2,1
Drive Type APPLE SSD SM128
Disk Test 64.77
Sequential 47.69
Uncached Write 25.43 15.61 MB/sec [4K blocks]
Uncached Write 61.11 34.58 MB/sec [256K blocks]
Uncached Read 45.33 13.26 MB/sec [4K blocks]
Uncached Read 163.30 82.08 MB/sec [256K blocks]
Random 100.92
Uncached Write 47.30 5.01 MB/sec [4K blocks]
Uncached Write 64.80 20.74 MB/sec [256K blocks]
Uncached Read 1398.42 9.91 MB/sec [4K blocks]
Uncached Read 426.44 79.13 MB/sec [256K blocks]

Those numbers are about average for the Samsung SSD that comes standard with the 2008 Macbook Air (google "APPLE SSD SM128" and xbench). Your SSD is not slower than normal; that is normal. This particular Samsung drive was just a poor quality SSD. You can't really improve it.

It's also not fair to compare it to the SSD in your Mac Pro. I bet the Mac Pro SSD is a different brand (which means a different controller, firmware, flash, etc.). Not all SSDs are made equal.

MultiFinder17
Jan 22, 2011, 07:21 AM
It feels like it has got progressively slower which I know is a problem

The Pro is getting like 200 on every test bar the one which is a bit lower at around 50. This is the 2008 Air with the standard Apple SSD

If you want to really add the zip back into your MBA, I'd give these OWC SSDs a serious look - I just got one for my 2009 Air, and it's amazing. I've heard all around the web that the SSDs that Apple uses out of the factory aren't all that high quality, and that it's often better to just get a cheap hard drive in it and upgrade to an SSD yourself later.

KPOM
Jan 22, 2011, 08:28 AM
Those numbers you got for your Rev B MacBook Air are broadly similar to the ones I got on my Rev B before I replaced it with a Rev D (which scores significantly faster, albeit still slower than Sandforce-based SSDs like those at OWC).

I don't know to what extent "reconditioning" the Samsung SSD would help. I didn't find out about digilloyd's DiskTester until I was about to replace my Rev B, and didn't think it was worth it yet to spend $40 when I was getting a brand new SSD. I'll re-run XBench in a few months to compare the SSD speeds but so far it has held up.

There are very few replacement SSD options for the Rev B since it used an uncommon connector. OWC has a $300 120GB option that offers similar speeds to the Toshiba drives used in the current Rev D (actually about 20% faster according to the manufacturer's claims).

KPOM
Jan 22, 2011, 08:31 AM
If you want to really add the zip back into your MBA, I'd give these OWC SSDs a serious look - I just got one for my 2009 Air, and it's amazing. I've heard all around the web that the SSDs that Apple uses out of the factory aren't all that high quality, and that it's often better to just get a cheap hard drive in it and upgrade to an SSD yourself later.

That's changing. The Toshiba drives that Apple uses aren't the fastest (they spec about 17% slower than Sandforce drives), but hold up decently to use according to the tests run by the Mac Performance Guide site and are much better than the Samsung drives they used to use. I've also read some reports on this forum (particularly the MacBook Pro forum) of people experiencing some glitches with the SandForce drives, so perhaps that's another reason Apple has stuck with Toshiba.