We believe in the long term value of Apple hardware. You should be able to use your Apple gear as long as it helps you remain productive and meets your needs, upgrading only as necessary. We want to help maximize the life of your Apple gear.
Since publishing this column, more facts have
come to light about the 2010 MacBook Air (MBA) and its solid-state
drives (SSDs). The SSDs are not soldered to the system board, as
I had originally believed, but use a new connector, which means they
can be replaced. The first SSD upgrades for the MBA. The drives appear to
the operating system as SATA drives, and it appears that Apple is
using 3 Mb/s SATA II, although the company has not confirmed that.
Where this column refers to the SSD as being on the system board,
make a mental note that it's connected to the system board via
a connector.
"The new MacBook Airs are faster than their predecessors."
That simple statement in
Macworld's benchmark report on the new MacBook Air (MBA) models
comes as something of a shock when you consider that it applies to the
1.4 GHz 11.6" MacBook
Air. In fact, it scores a lot higher than last year's 2.16 GHz
mode.
The raw numbers are there: The 11" MBA has an overall Speedmark 6.5
score of 85. The 1.86 GHz 2009 MBA, 54. The 2.13 GHz version, 63.
The biggest change in the MacBook Air is the move from slow 4200 rpm
1.8" hard drives to flash memory for data storage. Macworld reports
that duplicating a 1 GB file took five times as long with the 2009
model's hard drive as with the 2010 model's solid-state drive (SSD). In
other tests, the new drives came in at 21% faster.
But the surprising thing is that the processor intensive tests also
saw huge increases. Those tests aren't supposed to be impacted by hard
drive performance, the Core 2 Duo CPUs in the new MacBook Air are not a
quantum leap from previous versions, yet "the new 1.86 GHz MacBook Air
outperforms its predecessor in processor intensive tasks," according to
Macworld.
And Macworld is not alone. Primate Labs has benchmark results using
its Geekbench tests. The original 1.6 GHz MBA scores 2031. Last year's
1.86 GHz model rates 2444. This year's 1.86 GHz model achieves 2695,
and the 1.4 GHz model comes in at 2026, approaching results for the
original 1.6 GHz MBA.
What is going on here? How can SSD make such a difference?
Virtual Memory
In the old days, personal computers had a certain amount of memory
installed, and that was it. If you ran out of memory, you had to quit
one or more programs to make room. The amount of RAM was all you
had.
Then came virtual memory, which allowed you to reserve a certain
amount of space on the hard drive where you could swap data from RAM to
the hard drive and back again. That was a whole lot slower than using
system memory, but it meant that physical RAM was no long an absolute
limit.
There was a tradeoff. Enabling virtual memory let you do more, but
it also slowed you down. As programmers got smarter about it, they
began writing programs where rarely used bits of code would normally be
stored in virtual memory, leaving more physical RAM for real work.
The only way to improve virtual memory performance was with a faster
hard drive, one that could move data to and from system memory more
quickly.
And under old virtual memory schemes, such as the one used by the
Classic Mac OS (versions 1.0 through 9.2.2), you were limited to
whatever amount of drive space was reserved for virtual memory.
For Mac users, all of that changed with the introduction of Mac
OS X. You no longer had to specify how much drive space was
available for virtual memory - all free space on your hard drive was
available. And you could no longer disable virtual memory; it was an
inherent part of the operating system.
The Drive Matters
If you've ever booted the Classic Mac OS from CD, you know how
slowly it loads but how quickly it runs once it's finished booting. And
if you've ever booted Mac OS X from CD or DVD, you know how slowly
it loads and how slowly it runs even after the system is booted. The
problem is, OS X depends on virtual memory, and virtual memory
depends on a drive you can write to - CDs and DVDs are not writeable
and cannot be used for virtual memory, forcing OS X to get by with
whatever physical RAM is installed. (Another benefit of the MDA's
USB recovery drive is that it uses flash memory, making it a
writeable drive.)
For installing the operating system every year or two or recovering
from catastrophic drive failure (is there any other kind of drive
failure?), that's not such a big deal. It's not something you're doing
every day, every week, or every month. But for regular system
maintenance, we recommend a separate hard drive or drive partition so
you can avoid the Booting From the SuperDrive Blues.
A faster CPU means a faster system. Faster system memory means a
faster system. More system memory means a faster system, since it
reduced dependency on virtual memory. And a faster hard drive means a
faster system - the more virtual memory is used, the more important it
is.
2 GB Is No Longer Excessive
When Mac OS X first came to market in March 2001, you could install
and run it on a G3 or G4 Mac with 64 MB of memory, although Apple
recommended 128 MB. As users quickly discovered, more RAM let it run
more quickly by reducing dependence on slow virtual memory.
OS X 10.2 required 96 MB, Apple suggested a minimum of 128 MB, and
users recommended 192 MB as a realistic minimum - and 256 MB to 512 MB
strongly recommended. With 10.3, 256 MB to 512 MB became the
recommendation, and with 10.4
Tiger, you needed 256 MB and ideally had 512 MB to 1 GB.
As someone who uses Tiger daily, I can tell you that every bit of
extra system memory improves performance. I've boosted my dual 1 GHz Power Mac G4 from 768
MB (installed when I purchased it secondhand) to 2 GB in
incremental steps, and each additional 256 MB or 512 MB of RAM improved
performance.
Mac OS X 10.4.4 was the first version for Intel-based Macs, and the
Intel and PowerPC versions of Tiger could not run on the other hardware
platform.
OS X 10.5 Leopard was the last
version to support PowerPC Macs. Leopard required 512 MB, with
1 GB recommended, and the installer wouldn't let you put it on a
Mac with less than an 867 MHz G4 CPU, although workarounds were found. OS X
10.5 was the only version that could be universally run on both Intel
and PowerPC Macs.
I also use Leopard daily, and my Leopard Mac has less system memory
than my Tiger Mac. 1.25 GB of RAM used to sound like a lot, but it's
just adequate when you're running a dozen apps at the same time. This
Digital Audio Power
Mac (upgraded with a dual 1.6 GHz CPU card) only
supports 1.5 GB of system memory, and although it would help a bit, I
don't anticipate boosting memory any further. At this point I need to
start seriously considering getting my first Intel-based Mac.*
OS X 10.6 Snow Leopard,
released in August 2009, only runs on Intel-based Macs and requires at
least 1 GB of memory. It really needs more than that, and the
MacBook Air has always shipped with 2 GB as its only
configuration. Problem is, 144 MB to 256 MB of that is used for video,
leaving 1.75 GB for the operating system and software.
If you plan on using more than one browser, running Photoshop, or
having a lot of programs active at the same time, you'll be using
virtual memory in no time at all, which is why it's so nice that
Apple finally offers a 4 GB version of the MacBook Air (you have to
order it that way; user upgrades are not possible.)
It's That Much Faster
Where previous versions of the MacBook Air used a 4200 rpm hard
drive for virtual memory, the 2010 models use fast flash memory. It's
far faster - Macworld found copying a 1 GB file was five times as
fast on the new MBA's SSD compared with last year's hard drive
model.
Because virtual memory is always on, the speed of virtual memory has
always been a factor in OS X performance. Until now, we really
didn't see a huge difference because hard drives have latency and
physical limitations on how quickly they can read and write data. A
faster hard drive is somewhat faster than a slower one for virtual
memory, but not on the same order as the flash memory in the new
MBA.
Not only is SSD faster for disk-based tasks, but because virtual
memory is always on, it improves performance for memory-based and
CPU-based tests as well.
The Future of MacBooks
Steve Jobs said that the MacBook Air points to the future of
MacBooks, and it's already evident that solid-state memory is a quantum
leap over even fast hard drives in terms of boosting overall system
performance.
CPUs are slowly getting faster, and until now, SSDs have been used
to replace hard drives connected to a SATA interface. By putting flash
memory on the system board, there's no bottleneck in accessing data, so
flash-based MacBooks will boot more quickly, load apps more quickly,
open files more quickly, browse the Web more quickly (all browsers
cache data to the system drive), and overall do everything more quickly
without any change in CPUs.
In short, with the 2010 MacBook Air, Apple has shown us what a
significant bottleneck slow notebook hard drives have been. With the
possible exception of next revision to the consumer MacBook, expect all
future Mac 'Books to include SSDs.
Because Apple isn't competing on the low end of the notebook market
and designs its own system boards, it can afford to do this, making a
64 MB or 128 MB SSD standard on the MacBook Air - and probably 256 MB
and 512 MB on future MacBook Pro models.
Whither the Hard Drive?
I anticipate a future in which MacBooks no longer have a built-in
optical drive and no longer ship by default with a hard drive. That
said, I wouldn't be at all surprised to see Apple continue to offer
space for an internal notebook hard drive, providing additional storage
space for those who find SSDs too small for everything they do.
Within the coming year, I wouldn't be at all surprised to see flash
memory replace hard drives in the Mac mini and iMac, and I'd be shocked
if the 2011 Mac Pro doesn't have a system board flash drive, as this
would really unleash its performance. Hard drives will be for
additional storage.
Based on what we've seen with the lower speed CPUs on the 2010
MacBook Air, I look forward to the kind of speed boost we're going to
see in future MacBooks and desktop Macs.
System board SSDs will come to the PC world eventually, but that's a
world where most brands don't design their own system boards or
manufacture their own hardware, choosing to depend on other companies
to design and manufacture system boards, other components, and even
assemble the end computer in many instances.
The new MacBook Airs are faster than their predecessors thanks to
fast system board flash memory, and future Macs will have that same
advantage. That's Apple innovation in action!
* I've been using Google Docs spreadsheets for a
year or two now, and I recently accessed them on a friend's Windows
notebook. Now that I have seen how slow things are on my dual 1.6 GHz
G4, it's time to get serious about joining the Intel Mac world. I'm
hoping finances will permit that in the not-too-distant future.
Dan Knight has been using Macs since 1986,
sold Macs for several years, supported them for many more years, and
has been publishing Low End Mac since April 1997. If you find Dan's articles helpful, please consider making a donation to his tip jar.
Links for the Day
Mac of the Day: Yikes! Power Mac G4, introduced 1999.08.31. The only Power Mac G4 with PCI graphics was built on a modified G3 motherboard.
