Memory Pressure, Capacity Limits, and Ubiquitous Computing
 

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Hello! I'm David Schuetz.
This is where I ramble about...stuff.

Memory Pressure, Capacity Limits, and Ubiquitous Computing

One of the things I was most looking forward to with my new iPhone 5S was faster switching between applications. It seemed like my 4S always took 5-10 seconds to toggle between two programs, even simple apps. Jumping from Angry Birds to YouTube (to see what I’m doing wrong) and back again was agonizing.

Unfortunately, though the 5S is significantly faster, switching has in some ways become worse. The slowest reloads are faster, but I feel like I need full reloads more frequently. I’m convinced this is simply due to memory usage. Many applications (especially those with lots of full retina artwork) are taking the device to its RAM limits. No amount of new processor power can mask the fact that there’s just not enough memory in the device.

So it occurred to me a while ago — what if Apple can come up with a good way to load a program in memory in small chunks? Last year at WWDC, they showed off all kinds of processor and OS tricks to make OS X as power-efficient as possible. Could they do something similar for memory?

Rather than loading an entire application into memory at once, could iOS offer a way to let programmers break their apps into smaller chunks that are loaded only when needed? Kind of like the time-based grouping of operations in OS X, only focused on memory rather than CPU usage. Why should the code for managing app settings be in memory while the user is off shooting zombies? Do you really need chart generation code when we’re just editing text in a word processor?

If we’re able to do something like this, then all kinds of new things suddenly become possible. The oft-rumored “side by side” application usage could be a possibility, for one. I’m not sure that’d work otherwise, as the apps just seem to need too much RAM. Of course, Apple could double the memory in the devices, but then apps would just expand to fill that size as well.

Another thing that might then be possible is sort of an “iTunes Match” for applications. The OS would keep frequently used applications on the device at all times, but only “install” rarely used apps on demand. If you’re only downloading bits of an app at a time, as needed, then this might actually be feasible.

It’s interesting in a way — some time ago, there was talk about “Just In Time” delivery of applications over the internet. It’s possible this was part of the promise of Java — I may have blocked the precise origins of the concept from my memory. I distinctly remember thinking at the time, hell no, if I buy an application I want a copy of it locally, all the time. That I wouldn’t trust that I’d be able to retrieve my applications over the net like that.

Well, guess what? We skipped right over JIT applications and put all our data in the cloud instead. Kind of funny, when I think about it.

As long as I’m rampantly speculating (on the day that WWDC opens, no less — I really should get these thoughts out when they happen and not months later…), let’s take this line of thinking to its logical, yet absurd, conclusion. If all our data is on the cloud, and if all our apps can be downloaded from the cloud on demand…why do we even need “our own” iPads? Just authenticate yourself to the iPad, and boom!, it looks like your iPad, with all your apps and data coming down when you ask for them. Done using the iPad? Sign out, and boom! again, all the data’s gone.

Of course, Apple has not shown any indication that they want to follow the concept of “logins” on an iPad, but it’s an interesting thought anyway. Go to Starbucks, borrow one of their store iPads, work with it as if it’s your own, then log out and leave it for the next user. Apple’s already toyed with some of this, as you can configure an OS X machine to allow guests to log in using Apple IDs (though it’s obviously not doing this data / application magic at all). Also, something akin to this was always hoped for with NeXT machines (though in that case, you’d carry your computing world around on a 256MB magneto-optical disk, which was damned cool for 1988).

I understand that this sort of change would be difficult to achieve, and possibly impossible in practice. But it’s certainly interesting to think of. And, putting aside crazy ideas about “logging in” to a friend’s iPad and replicating your entire environment on the fly, I still think that something like this would be very useful (and may even be required) for making apps much more responsive, especially when switching between applications.

And we could even use the iWatch and BTLE for seamless authentication!