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iPad iPad Air 2 has 2 GB RAM and a three core A8x processor
- Thread starter Charliebird
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2GB of RAM will absolutely improve Safari reloading, more than you realize.
With no apps in memory, a retina display 64 bit iPad requires 600-800 MB of its 1000 MB available RAM. Running Safari adds 50-100 MB RAM, and keeping other light apps in memory uses up more. Websites with images in Safari use around 75 - 150 MB RAM each, and use up even more RAM if the website includes 4x images for retina displays. When a webpage is not displayed, iOS compresses the webpages that are currently stored in RAM. When the RAM for the iOS system + compressed applications in memory + Safari application + compressed webpages + the displayed uncompressed webpage is greater than the total RAM, applications and webpages are offloaded from memory.
There is no problem or memory leak in Webkit or Safari. All web browsers use at least this much RAM to load websites. Safari/webkit on iOS and OS X actually use less RAM than the OS X Chrome and Firefox rendering engines. The reason you see tab reloads on iOS, and not on virtually all other operating systems, is because iOS does not offload webpages to swap memory. And there is a very good reason for this. Mobile devices such as iOS devices and Android devices use NAND flash, which is extremely slow, write speeds are 10-20 mbps. Desktop and laptop HDDs and SSDs are much, much faster than this. Thus, swapping webpages to disk with this slow write speed would considerably slow down the whole iOS.
With 1GB RAM, an iPad would have 700 MB taken by iOS, 75 MB taken by Safari.app, 125 MB taken by the viewed webpage, and say 100 MB taken by 2 image-heavy compressed webpages or 5 less intensive webpages. Which means 3 heavy websites stored in memory or 6 less heavy websites.
With 2GB RAM, an iPad might have 750-800 MB taken by iOS, 75 MB taken by Safari.app, 125 MB taken by the viewed webpage, and we would have 1000 MB for compressed webpages. So this means 21 heavy websites stored in memory.
Like comparing a lightning bolt to a sloth. The DDR3 RAM in iPad Air/iPhone 5S is 8000 MB per second to write data. The dirt cheap NAND flash storage Apple uses in these iOS devices is 80 mbps to write data. These speeds are two orders of magnitude different. Past iOS devices don't use the more expensive SSDs (solid state storage) found in Macbooks, which write data at 700 mpbs.
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Exactly. Looks like Apple has started to use more expensive SSDs instead of the NAND in their latest iPad. NAND storage is a big limiting factor in iOS device performance, so this move makes sense for Apple. This adds a realm of improvements including increased OS speed and opens up RAM paging options as well (not that this is needed, with 2GB RAM).
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20 Mbps? That's not even particularly good broadband speed these days!
Got a Samsung EVO in my lappie and that is lightening. What a silly thing to scrimp on though; thought Apple was all about making sure there was no crud under the carpet either.
Well, it's not Apple's fault. A few years ago, NAND flash was the only viable option that was tiny enough to fit into a small mobile device. Only recently have SDDs come down in price that include a smaller storage capacity, and are smaller in size.
NAND speeds (toward bottom)
SSD speeds
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It would be nice if there was an "Oh right, we forgot to mention the Lightning connector uses USB 3 now." moment.
But I guess just being able to keep USB 2 bandwidth close to saturated would be a nice step up from what my iPod Touch 4G does now.
But I guess just being able to keep USB 2 bandwidth close to saturated would be a nice step up from what my iPod Touch 4G does now.
The vast majority of iOS device users rarely, if ever ,sync to a computer via USB, so I really doubt that upgrading the Lightning connector to USB 3.0 is a high priority.
SSD and NAND are not mutually exclusive technologies and, in fact, as of right now almost every single SSD is made of NAND memory with the only exceptions being RAM-based solutions not used in products like these. The main difference in performance comes from the controllers and how memory is accessed in parallel.
And as a sidenote, the motivation for Apple to improve their flash storage speeds is likely increasing WiFi/LTE throughput as the storage quickly becomes the bottleneck moreso than the radio itself for any application that stores data as it's received (which is nearly all common uses of the network thanks to caching.)
Which is why I set my laptop browser cache to RAM only - not a problem with 8 gigs of it. Half of that will do for the iPad though thanks.
True... the 80 mbps sequential write speed of NAND flash in the iPhone 6 inhibits the AC wifi speeds. That definitely is a bottleneck Apple needs to fix for the iPhone. But at least they fixed it in the iPad Air 2.
Possibly, but with the high capacity models I'd guess that there are many high volume USB syncs (i.e. to fill up with and change over video) where transfer speed is an issue due to the amount of data being synced.
I'm not saying that it will (or should) be a high priority, but considering how many people use their iPads to watch video, data transfer speeds via USB are an issue to many people.
It does boggle my mind as to why they simply sit back on tech, especially something so simple to include.
Are there are any browsers for the iPad that don't have this issue on the iPad with reloading tabs? I don't know that's why I'm asking.
There's no rule for even/odd #'s of processors. You often see ram in even numbers to utilize multiple data channels. The xbox 360 had a tri-core custom processor as an example.
Are you sure about these numbers? From what I have read elsewhere iOS 8 takes about 300-400MB.
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Indeed, and PS3 had 7 active cores.