I decided to test out my theory. I began by restarting my system (a
dual 2GHz G5 PowerMac with 2GB of RAM), then rendering out my After
Effects movie again, with no other applications open. I got an almost
identical render time as the first render. I then opened Safari, and
opened 5 random sites in tabs (digg.com, cnn.com, myspace.com,
macenstein.com (of course) and virb.com). I figured these represented a
good mix of the type of sites I visit, as well as sites with differnet
types of layouts and memory requirements. I clicked around a bit in
each site to build up a little cache action, then re-opened After
Effects and rendered the scene again. The render time was almost
exactly the same 15 minutes longer that I experienced the first time.
The next step was to figure out if this slowdown was only due to
Safari, or just web browsing in general. So I made a stripped down test
project for After Effects (so I didn’t have to spend 30 minutes waiting
for each test to complete) and did the same “fresh reboot, open After
Effects, render, quit, open Safari, open After Effects, and render”
test as before to get my baseline times. Using After Effects sans ANY
browser scored a render time of 154 seconds. After Effects with Safari
running got a time of 271 seconds.
Next, I repeated the test with Firefox instead of Safari, and was
very surprised to see that Firefox added only 6 seconds to After
Effect’s render time. (See Below)
Above: Results on a PowerMac rendering an After Effects project,
then again with Firefox and Sarafi open. The PowerMac ran almost 76%
slower with Safari open.
I decided to grab the ol’ stopwatch and then try some Photoshop
tests. I recently had to make a series of banners for a project I was
working on, so I used one of them (a 1.72GB 50 x 32.5-inch Photoshop
file at 300 dpi) for my test. First, I tested how long it took
Photoshop to launch and open the file via double-clicking. Next, I
timed how long it took to do a “Save As” PSD. I then quit Photoshop and
repeated the tests with both Safari and Firefox. Results are below.
Above: Results on a PowerMac opening and saving a 1.72 GB file,
then again with Firefox and Sarafi open. The system took 40% longer to
open the document and 49% longer to save it with multiple sites open in Safari.
As you can see, Photoshop gave a similarly dismal performance while
Safari was running, particularly during the “Open Document” test, where
it added a full 97 seconds to the process.
I did one final test in QuickTime, exporting a 2 minute full screen
video clip to iPod. I was pleasantly surprised (and yet somewhat
baffled) to find that Safari had no adverse effect at all on the export
time. I got the exact same 3 minute 44 second time for all 3 tests. I
was sort of surprised as I figured compressing a movie would use
similar function calls resources as rendering an animation from After
Effects. So apparently this issue is somewhat application specific
(perhaps even exclusive to Adobe apps? Insert conspiracy theory here
For the record, all tests were done twice, and the average times
were used. My Safari installation should be fairly clean, as I have not
installed any odd plug-ins or such. Pretty much the factory default
A “Universal” problem
As one final test (and because everyone loves graphs!) I repeated
all tests again on a Quad-core 2.66 GHz MacPro, with 2 GB of RAM. Of
course both Adobe apps had to run under Rosetta, as neither is a
Universal app yet. While in some cases the difference is not AS great
as on the PowerPC model, you can see that there is still a sizable
performance hit when using Safari (and remember, the Mac Pro has 2
extra processors available to handle the “demands” of Safari).
Above: Results on a Mac Pro rendering an After Effects project,
then again with Firefox and Sarafi open. The Mac Pro ran 21% slower
with Safari open.
Above: Results on a Mac Pro opening and saving a 1.72 GB file, then
again with Firefox and Sarafi open. Performance hits of 37% and 29% for
the “Open” and “Save As” tests.
It was nice to see that despite both After Effects and Photoshop
being PowerPC apps relying on Rosetta, After Effects actually rendered
slightly faster on the Mac Pro than the PowerMac, and wasn’t that out
done in the Photoshop “Open” test.
The interesting thing about these results (to me at least) is that
both Firefox and Safari were simply open during their tests. I was not
actively “surfing”, ie. clicking on things, moving windows
etc. It seems to me that a background application, especially one that
should not really be doing anything all that processor-intensive even
when in the foreground
, should not hog system resources the way Safari apparently does. If Firefox can play nice, why not Safari?
I suppose as a final disclaimer I should say that while I did
everything I could think to keep the tests fair (using the same web
sites, running multiple tests and so forth) it is possible that both my
work and home machines (with different processors, graphics cards,
software installations, etc.) are both somehow uniquely wacky, and I
have the only 2 machines on the planet that will bear out these
results. It could also be my choice of sites, although the fact remains
Firefox had no problem handling them.
To that end, I would encourage anyone with these apps, a stop watch,
and too much free time to conduct their own tests. I would also love
feedback on performance hits on other apps when using Safari, such as
some 3D applications. The fact that both affected apps were Adobe apps,
and QuickTime (an Apple app) was NOT affected is a little strange to
me. For those of you looking to conduct your OWN tests, I would like to
point out that simply opening Safari and conducting tests will not
yield too much of a difference; you need to have at least a few open
tabs (I used 5), and I would suggest visiting some “intense” sites. I
chose MySpace as one of my test sites because I consider it to be the
worst coded page out there, with tons of flash ads and other gunk that
can stop up a browser.
So what does this mean? Well, for most people, not a lot. If you are
just using your computer for Word, e-mail, and web browsing, I doubt
there is much of a noticeable performance hit. It really seems that
only “Power Users” (if I may be so bold as to lump myself in that
group) will be affected, and possibly not even all “power” apps will be
affected (as shown in the QuickTime test).
For ME, however, these results means that while Safari is still my
browser of choice, if I am going to kill time while large,
time-critical projects are rendering, I will be using Firefox. Or
better yet, another computer.