What application are you most looking forward to?

archie

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For those of you who remember the big virtual memory discussion, turns out the iphone DOES have virtual memory. It operates a bit differently from the desktop version, though, so you are limited to physical memory space.
You cmaier, were one of those (surur and mikec too of course) that berated me for stating what everyone will now be seeing with the SDK.

And so you will also see that it does indeed have 1GB of RAM, but not for the virtual memory as you typically think of it, as you just stated. It is memory that actually lets the thing compile on the fly and store the stuff there.

But of course I'll never get an apology. :rolleyes: I just get banned. :mad:
 

cmaier

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You mis-remember, Archie. I stated all along that there was virtual memory, and I was opposed by Surur and others. I don't think I've ever agreed with Surur about much of anything.

There is no "compile on the fly." GCC 4 is used to compile on the desktop. Perhaps you are using "compile" in a less technical sense?

And you get banned not for your positions on things, but for making personal insults.
 

archie

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In response to me you had said:
An 8:1 cache to RAM ratio would be unheard of (but would prove there is VM - otherwise 7/8 of that memory would at all times be empty).

And any on-chip memory would have to be cache (particularly since otherwise there is no point added the 128MB external memory).

Archie, as usual, makes no sense, but his pedantic tone is at least amusing.
Then on the next page of that thread I had said:
archie said:
it was I that was derided and discounted for being the first to say that the iPhone would be easy to use one-handed... ...I'll stop tooting my own horn now but it seems I was right about a great many things.
To which you respond:
And wrong about so many more.


Anyway... in regards to the compiling on the fly, I was speaking of the JIT which that Apple uses which only places the code necessary into memory. Extremely efficient. Small footprint. No paging.
 

archie

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And you get banned not for your positions on things, but for making personal insults.

If I get banned for making insults, what happens to the people that made comments like these directed at me?



Amy Winehouse callled...she wants her crack pipe back.

You like to lie, as you are patholgoically incapabale of separating your incorrect interpretations from reality.

This all comes down to an inferioroty complex because you were a Mac user in a world of PCs. (How sad is that...)

Take the lips off the crack pipe...you obviously have not done even one bit of real research.

I guess you aren't just on crack, but meth and special-k too.

I was going to respond point by point, but it doens't matter. You just make up the fact to suit yourself (and if you even read, I gave you laptop prediction regardless of size.)

you have no fargin idea what you are talking about.

Archie is back and still spouting nonsense

You really, really should lay off the Kool Aid.

As long as you want to come to class, I will continue to school you accordingly.

I've been waiting for you to come back so I could laugh at you!

the best argument against crystal meth use that I've ever seen.

Archie, considering your problem, its not surprising that you managed to read only half of RIMM's press release.




It goes on and on and on.

I am an idiot and have no idea what I am talking about,
I have "Downs Syndrome",
I am "unable to function in real life",
I am "uninformed",
I am a "Liar",
I "Go off topic and don't admit that I lie",
I "double lie",
I "have problems beyond lying",
I "misrepresent the point",
I state nothing but "logical fallacies" (don't even know what that means)
I am "completely wrong in every statement" that I make,
I have no regard for the law and will be prosecuted,

That last one in particular makes me laugh.
 

oalvarez

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i gotta agree with you...that last one is quite funny.

hope all is well with the bunch of you

ps: WHY CAN'T WE DELETE MORE THAN ONE MAIL MESSAGE AT A TIME though? how many updates have we seen and still nothing.....ugh!!!
 

cmaier

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In response to me you had said:

Then on the next page of that thread I had said:

To which you respond:



Anyway... in regards to the compiling on the fly, I was speaking of the JIT which that Apple uses which only places the code necessary into memory. Extremely efficient. Small footprint. No paging.

You lost me. "Placing only the code necessary into memory" is called "demand paging." You say this is not paging? But that's exactly what it is. Unless you are talking about something else, again. (It's sure not "compiling," which is the translation of source code into machine code).
 

cmaier

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i gotta agree with you...that last one is quite funny.

hope all is well with the bunch of you

ps: WHY CAN'T WE DELETE MORE THAN ONE MAIL MESSAGE AT A TIME though? how many updates have we seen and still nothing.....ugh!!!

Deleting more than one at a time was actually announced in 2.0.
 

MacUser

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To get back to the original topic....

I am shocked the MacWorld post missed a password storage app like SplashID that works on both Macs and PC's.

PLEASE, PLEASE, PLEASE....I've become addicted to it.

Love,
A MacUser with an iPhone
 

burnsaa

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What about being able to attach multiple pictures in an email? If I took a couple pictures and want to email them to someone I have to send two or three emails :thumbsdn: that should be fixed along with deleting multiple emails.
 

oalvarez

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What about being able to attach multiple pictures in an email? If I took a couple pictures and want to email them to someone I have to send two or three emails :thumbsdn: that should be fixed along with deleting multiple emails.

another stupidity....but much less so than not being able to delete more than one email message at a time
 

surur

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For those of you who remember the big virtual memory discussion, turns out the iphone DOES have virtual memory. It operates a bit differently from the desktop version, though, so you are limited to physical memory space.

What does this mean?

Surur
 

cmaier

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"To manage program memory, iPhone OS uses essentially the same virtual memory system found in traditional desktop systems." - Developer's documentation.

Essentially, each program has access to its own virtual memory space. The difference is that in desktop systems dirty pages are written back, whereas in iphone clean pages are deleted. This has implications in how one would design software and use memory, because your working set (memory you are actively changing) cannot be bigger than physical memory.
 

surur

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"To manage program memory, iPhone OS uses essentially the same virtual memory system found in traditional desktop systems." - Developer's documentation.

Essentially, each program has access to its own virtual memory space. The difference is that in desktop systems dirty pages are written back, whereas in iphone clean pages are deleted. This has implications in how one would design software and use memory, because your working set (memory you are actively changing) cannot be bigger than physical memory.

While I understand this would allow the iPhone to run a collection of larger apps than the DRAM can hold by itself, this is only similar to eXecute In Place, and not the virtual memory as I was debating it.

This makes a joke of all the people who said they were reserving a few 100 MB of storage for swap space, which apparently increased their stability via the placebo effect.

As I was insisting all along also, there is a hard limit to how many web pages can be loaded at the same time, and seeing how they are full web pages, the number is not that big.

Surur
 

cmaier

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This is not "only similar to execute in place." It works for both code and data. For example, if memory holds X, and I have 2X of static data to display (for example, pdfs), I can display them so long as all 2X is not being shown at once. Alternately, if I am randomly modifying a huge block of memory, as long as it's less than "X" I still can simultaneously access more than X of static data. The only difference between this and desktop VM is that in desktop VM, if I want to randomly modify greater than "X," the VM automatically swaps out stuff I've modified. A programmer can still achieve this behavior on iphone by arranging data so that the dirty code pages always fit in memory.

As the document says, it is virtually identical to virtual memory on desktop machines, other than in deciding how pages are freed.

Note, too, that if you ran out of space for swap, you would be hosed in the iphone system, as it would have nowhere to put clean pages. Nothing about this scheme suggests a "placebo effect" (though I suspect it was one).
 

surur

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Note, too, that if you ran out of space for swap, you would be hosed in the iphone system, as it would have nowhere to put clean pages. Nothing about this scheme suggests a "placebo effect" (though I suspect it was one).

Arnt "clean pages" in this scheme pages that are already mirrored in the file system by virtue of being installed or downloaded there e,g, apps and downloaded pdf's for example. As you said, data thats generated by an app but not saved are never swapped automatically to flash.

There is no swap file.

Surur
 

cmaier

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There is indeed a swap file, as the organization of data in various files has little to do with the organization of data in memory. Seldom can you simply "page in" a file such that the first byte of the file is the lowest byte in contiguous memory, the next byte is next, etc. So even clean pages need to be written to swap; this prevents the programmer from having to manually re-calculate what goes where. Instead, a contiguous block of swap can directly be paged (copied) into a contiguous block of RAM.
 

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