4 ms·

i'm amazed and hurt that dalvik doesn't do inlining (but if JIT will need a few runs to get going... not unreasonable on a phone, if the app can stay resident i

by hyp0 13y ago

i'm amazed and hurt that dalvik doesn't do inlining (but if JIT will need a few runs to get going... not unreasonable on a phone, if the app can stay resident in memory) for my fellow perplexed: ART is a java runtime (dalvik alt) https://source.android.com/devices/tech/dalvik/art.html https://source.android.com/devices/tech/dalvik/art.html impressive improvement, x2 dalvik (on this one case...) BUT for similar GHz (2.3 vs 2.6), intel is x2 to x8 times faster than ARM...

fredgrott 13y ago
yes, but is not the battery performance worse for Intel's mobile cpus compared to arm? And side note, we have not seen 54 bit arm cpu performances yet as well
- hyp0 13y ago
  oh yeah, for sure. per mWh, ARM wins. i just meant they aren't grabbing raw performance any time soon... of course, to 'disrupt', it doesn't need to be as fast... just fast enough for what people need. so the Q is: what performance do people need? (related: what tasks do they need to get done?) for me... i've been coding on, and browsing with, a dual core 1.2GHz cortex 9.... it's fast enough for what I've been doing. (you need a bluetooth keyboard though)
higherpurpose 13y ago
It's not "Intel". Maybe Core i7. And even those chips have a wide variety of performance. Saying "Intel" implies any Intel chips is that fast, when that's not the case.
- Symmetry 13y ago
  Even "Core i7" doesn't mean much, since that's marketing lingo that means different things for laptop and desktop, and doesn't cover all the architectural changes that have happened from Nehalem to Haswell.
nly 13y ago
> dalvik doesn't do inlining (but if JIT will need a few runs to get going...) Is Dalvik actually a JIT these days? I thought it was just a bytecode interpreter with a register based VM. In any case, ART seems to be heading down the AOT path, which I think still makes sense in a mobile setting.
- Scaevolus 13y ago
  Dalvik has had a JIT since Android 2.2. It's quite limited relative to HotSpot due to memory constraints.
zobzu 13y ago
well also no intel gcc test
green7ea 13y ago
When comparing the intel and arm architectures, GHz doesn't mean much. Transistor technology has evolved to a point where most processors are clocked in that area. The reason that the intel processor is so much faster is that with a higher power envelope, you can have extra transistors. There transistors can be used to have better branch prediction, have better prefetching, have better SIMD instructions and have more cache. This is what really impacts performance. If you compare the performance per watt of both processors you see that they are somewhat similar. Keep in mind that ARM processors are also made to be much cheaper than their intel counterparts. Both ARM and Intel do a stellar job in their respective markets.

by hyp0 13y ago

fredgrott 13y ago

yes, but is not the battery performance worse for Intel's mobile cpus compared to arm? And side note, we have not seen 54 bit arm cpu performances yet as well

hyp0 13y ago
oh yeah, for sure. per mWh, ARM wins. i just meant they aren't grabbing raw performance any time soon... of course, to 'disrupt', it doesn't need to be as fast... just fast enough for what people need. so the Q is: what performance do people need? (related: what tasks do they need to get done?) for me... i've been coding on, and browsing with, a dual core 1.2GHz cortex 9.... it's fast enough for what I've been doing. (you need a bluetooth keyboard though)

higherpurpose 13y ago

It's not "Intel". Maybe Core i7. And even those chips have a wide variety of performance. Saying "Intel" implies any Intel chips is that fast, when that's not the case.

Symmetry 13y ago
Even "Core i7" doesn't mean much, since that's marketing lingo that means different things for laptop and desktop, and doesn't cover all the architectural changes that have happened from Nehalem to Haswell.

nly 13y ago

> dalvik doesn't do inlining (but if JIT will need a few runs to get going...) Is Dalvik actually a JIT these days? I thought it was just a bytecode interpreter with a register based VM. In any case, ART seems to be heading down the AOT path, which I think still makes sense in a mobile setting.

Scaevolus 13y ago
Dalvik has had a JIT since Android 2.2. It's quite limited relative to HotSpot due to memory constraints.

zobzu 13y ago

well also no intel gcc test

green7ea 13y ago

When comparing the intel and arm architectures, GHz doesn't mean much. Transistor technology has evolved to a point where most processors are clocked in that area. The reason that the intel processor is so much faster is that with a higher power envelope, you can have extra transistors. There transistors can be used to have better branch prediction, have better prefetching, have better SIMD instructions and have more cache. This is what really impacts performance. If you compare the performance per watt of both processors you see that they are somewhat similar. Keep in mind that ARM processors are also made to be much cheaper than their intel counterparts. Both ARM and Intel do a stellar job in their respective markets.