Why does OSX take longer to initially load up a program?

[sindows]

I've had this experience with OSX on slow and fast hardware so hardware age is not the issue. Every time OSX is restarted, programs like iWork and Office'08 take ages to load. However once you quit and then load then again, its much quicker. Is there any reason for this? I'm not taking about just closing the window either. In Linux or Windows, the amount of time it takes a program to load once you've quit out of it is the same no matter if you've just booted or your computer has been on for the entire day.

 

[theblackbox]

on my desktop, everything loads fast, first time, last time, every time. even fsc2 programs load quickly on my desktop. i see what you are talking about on my laptop.

 

[KeypoX]

im not 100 percent but i think once you open a program in mac, it keeps it in memory. While windows pre loads a lot of stuff in memory, frequently used programs. Super fetch i think its called.

 

[ViRGE]

Originally posted by: KeypoX
im not 100 percent but i think once you open a program in mac, it keeps it in memory. While windows pre loads a lot of stuff in memory, frequently used programs. Super fetch i think its called.

That's a lot of the reason, yeah. Mac OS X has a pre-binding mechanism, but no pre-fetching mechanism. So a program being opened for the first time will always have to be fully loaded off of the disk.

It's still a bit slower than Windows though even after accounting for pre-loading. I get the impression that Mach-O binaries just take more work to load.

 

[hiromizu]

Windows does this too. I don't know what you're going on about.

 

[TheStu]

Originally posted by: hiromizu
Windows does this too. I don't know what you're going on about.

Which part, the holding in RAM bit?

If you are referring to Windows as Windows XP and earlier then that would be why, or at least why they start up slowly. You use Vista for a while and SuperFetch should pick up on what you use on a regular basis. Emphasis on should. I never really use Windows all that much, so I can't say, and what I do use Windows for, it won't SuperFetch those programs (namely games).

 

[timswim78]

I tend to agree with the OP. My windows machine is a single-core laptop running XP with 1GB of RAM, and I also have an iMac C2D with 4GB of RAM. From a fresh boot, Firefox, iTunes, Picasa, etc. take considerably longer to load on the iMac.

 

[Kmax82]

Yea. Initial loads on programs are slower on OS X. I don't know the technical applications of this, but generally once I start a program I will leave it open all day. This leads to essentially no loads at all. I open a new Firefox window in half a sec, switch to Photoshop in about 5 secs (if I had something else in memory). So while it does take a little longer to load a program, I find it much quicker once that is done.

 

[Nothinman]

In Linux or Windows, the amount of time it takes a program to load once you've quit out of it is the same no matter if you've just booted or your computer has been on for the entire day.

No they don't, once started they'll stay in memory until the OS needs to evict them so they startup with very little to no I/O after the initial startup.

 

[sourceninja]

I never shutdown my mac, maybe this is why I never notice a start up delay. I click it opens. Typically as fast as that. Except itunes. itunes for some reason takes forever.

 

[Kmax82]

Originally posted by: sourceninja
I never shutdown my mac, maybe this is why I never notice a start up delay. I click it opens. Typically as fast as that. Except itunes. itunes for some reason takes forever.

Yea, I shutdown my Mac, maybe once a month, if that.

The other program that does this is Firefox with lots of add-ons. A default Firefox install is super fast, but once I add in all the extra tools, it really slows down the start up. Safari 4 is also much slower to start than Safari 3 was, but I just attribute that to it's beta status.

 

[BriGy86]

On the Mac notice the dock. If you have 10.4 some programs will have a black arrow below them which means they are technically running. In OS 10.5 its a glowing light blue dot. You'll notice that if you make a point to click file then quit, they disappear. That is because the program is actually closing entirely.

 

[Kmax82]

Originally posted by: BriGy86
On the Mac notice the dock. If you have 10.4 some programs will have a black arrow below them which means they are technically running. In OS 10.5 its a glowing light blue dot. You'll notice that if you make a point to click file then quit, they disappear. That is because the program is actually closing entirely.

I'm not quite sure why you felt you needed to give us a lesson in OS X Application 101, but the OP clearly stated that he was not referring to just "closing the window". 😉