It has been a few days since the announcement and after taking several
quick looks outside, I see the sky has not fallen very much, folks are
not walking down the street kicking puppies and kittens while wailing
and gnashing their teeth. In other words, the world has not ended yet.
Yet :^).
After the initial announcement I wondered out loud here why Apple was
going to take so long to make the transition. After all, the evidence
seems to be that things are pretty much ready to go, and there are lots
of benefits to Apple and Intel working together, such as access to the
good graphics cards, possibly a faster path to new cutting edge tech
like the ripping fast SATA2 drives (SATA gave SCSI serious heartburn,
SATA2 is the death knell for SCSI) etc. We even have the Intel "mini
pc" as a good prototype for the Mac Mini, not to mention being able to
have those 10 hour battery lives on the laptops. So why the wait? Apple
seems to be ready for Intel.
After looking things over, I believe that Intel is not ready for Apple.
Yet. Not on the high end. We need AltiVec or a darned good replacement
for it.
The G5 machines are really good values for the money, better than Intel
based offerings at that level. I will use PhotoShop as an example. If
you only import jpegs from a scanner or small digital camera, crop
them, maybe resize them for email or for the web, then just about any
app that imitates iPhoto works well for you. Heck, iPhoto is great at
this and comes with a decent database manager that allows you to
catalog your collection nicely (as long as it is not too large). But
start to do very serious manipulations to these images and then you
need the power that PhotoShop (or one of its competitors offers).
Reading through the initial reports, Rosetta tells PPC apps that they
are running on a G3 machine and the PPC apps "drop-down" to using only
G3 code (G3 computer code does not use the AltiVec units but yes,
PhotoShop will run on a G3). So the transition should not be a problem.
Uh, yes it will. Not from a "I cannot run my current software on the
new machine" level, but from a "It is not worth it to run my current
software on the new machine" level. These editing apps rely heavily on
AltiVec. It has been around for some time, the programmers understand
its oddities fairly well, the compilers that use it have matured nicely
(are pretty well optimized). G5 chips, while not using the entire
AltiVec instruction set, use so much of it that you can safely say it
has an Alitvec unit in it. Many of today's digital cameras are storing
files that are around six or eight mega-pixels. These files open up to
being around a 25 to 40 MB sized single layer in PhotoShop. [Note:
these sizes are common ones in 35mm equivalent digital cameras, not the
"top end" 35mm equivalents, nor even close to the file sizes that the
film users get when they do what is called a drum-scan of their
images.] Combine several of these layers together, it does not take
many to get a 2 or 300 MB sized file. Now start doing things on that
file and you need some serious number crunching ability -- at high
speed. This is where the G4 and G5 machines really shine, because they
have the AltiVec units in them. While you might say that $3000 for a
top end G5 mac is a lot of money (it is!) it is quite a value. To match
the performance using the Intel based chips you have to spend a bit
more to get the machine to keep up with the Mac, you have to spend
quite a bit more to only beat the Mac by fractions of a minute or
second and only in some areas. Only the very large projects will see
enough time savings to make buying the Intel systems a viable
proposition. For most, the top end G5 Mac is the better value.
"But", you say "The editing apps will run on a G3 machine and so they
should do okay on the new high speed Macintels. Or heck, just get the
re-compiled version of the app, it will run fast."
Set a G3 machine next to a decent Pentium machine and try running
PhotoShop on them. You will quickly find that in that setting, MHz does
matter. A lot. The Pentium will eat the G3's lunch for it, because it
is way faster. Up to this point, IBM (they make the G3 chips) does not
offer a 6 GHz G3 chip in their catalog, which is what you will need to
win that race. As to the second point, yes, the recompiled version
should run and be quite peppy. But we will need the very top end Intel
chips to do this. Suddenly our $3000 top end Mac becomes a $4000 or
$5000 machine -- the same as the current Intel based stuff and the
Mac's cost-performance value is lost.
That may be why the transition will take a while. So that Intel can
give Apple something on the top end that is affordable. Something that
replaces AltiVec or makes its advantage negligible, so negligible that
we do not need it any more.
"But Jerry", you say, "Those PhotoShop comparisons are really contrived
and just set up to make Macs look good. No one really does that stuff
anyway, right?" The examples are not that contrived, they deal with
regular daily things folks do with editing apps. Here is a nice example
to illustrate that. Folks that have been working with digital photos
have been for some time combining different exposures together to get a
single image that has what is called an extended dynamic range (the
combined image has lots of detail in the dark and bright areas,
something that is tricky to do with the separate single exposures -- at
the 35mm level). This technique is so common place that that a new file
format has been invented to accommodate the various approaches (the
approach is now called High Dynamic Range -- HDR). The latest releases
of the editing apps are now giving us tools to make the work involved
easier, it is very computationally intensive. Unless you use the very
latest updates, you used complicated masking procedures to hide or show
portions of the images, again a process that is very intensive on a
computer. The AltiVec based Macs, while not making this effortless,
make this make this doable in a reasonable amount of time. A file that
might take four or five hours to work on, on a G5, will take days to do
on a G3 Mac using the older masking approaches. How long will it take
using the new tools? Probably a while. If you have CS2 you can find
out. Navigate to your PhotoShop extensions folder and pull out the
extensions with the AltiVec names in them (for kicks also pull out the
ones that have the Multiprocessor and PPC names in them). Restart PS,
open a file and start to do some work. Whoa! Talk about a major
slow-down! Major to the point of being like swimming in molasses - you
are now running PS in G3 mode. Yuck. This "contrived example" is what
is common today. What will be done in the next few years is open to
guessing.
"Jerry, are you sure this is this not yet another contrived example?"
Nope, visit here to see some of this in action:
http://www.hdrsoft.com/
This is one of Adobe's competitors showing their tools in action
against PhotoShop (I am not affiliated with either company!!!!!!!)
So I think that Apple is waiting for Intel to show something both good
and affordable on the high end and that is why the transition will take
a while. These comments and speculations are avery valid for video and
audio editing apps as well, including Final Cut, etc. They need AltiVec
too, more so than PhotoShop does.
"What about all of those high end apps that do not use Altivec?" I
think those will immediately do well with the re-compile and run on the
new hardware. Even the ones that use PPC code without using the AltiVec
stuff. Keep in mind the compilers for the G5 are essentially brand new.
The AltiVec stuff is good but as I mentioned that end is pretty much in
a mature state. The integer part (these things Intel does a good job
on) on the G5 has lots of room for improvement. These integer
instruction sets are not even close to being very well optimized
(fine-tuned for speed and stability). So that switch should go well and
keep the database folks pleased. Though I guess we will not get to see
how well Oracle really would run if it had been set up using a mature
development package on a G5 system.
For the time being (next two to four years) the G5 Macs will still be a
solid value for the money.
Jerry
-----------------------------------
Someday, I will come up with a clever signature line. I am not sure if
I will use it or not, but I will come up with one.
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