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iPad apps have access to 256MB of RAM, single core processor

First things first: The iPad is fast.  Web browsing is fast, games are fast, app switching is also fast, especially compared to the iPhone.  

But if you think there are some crazy specs under the hood, you might be in for an unpleasant surprise.  Doing a little coding, we’ve discovered that iPad apps only have access to 256MB of RAM and the processor thinks it is a single core (probably ARM Cortex A8) processor.

You can verify these results by building an app with the following code in Xcode: 

int getRamSize()
int     count ;
size_t  size=sizeof(count) ;

if (sysctlbyname(“hw.memsize”,&count,&size,NULL,0)) return 1;

return count;

The relatively small CPU requirements (first speculated by Ars’ Stokes) might also explain the iPad’s incredible battery life.  So how does Apple get applications to run so fast?  Thanks Thomas!

Updated: Clarification of physical RAM vs. accessible RAM.  Craig Hockenberry found similar RAM results.  (below)

When using sysctl() to query the amount of memory available to the iPhone OS, the following values are reported:

Kind Bytes Megabytes
Physical (HW_PHYSMEM) 258,998,272 247 MB
User (HW_USERMEM) 210,284,544 200.5 MB

Again, it

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