By: Michael S (already5chosen.delete@this.yahoo.com), July 11, 2013 4:33 am
Room: Moderated Discussions
none (none.delete@this.none.com) on July 11, 2013 4:44 am wrote:
> Klimax (danklima.delete@this.gmail.com) on July 11, 2013 3:00 am wrote:
> > none (none.delete@this.none.com) on July 11, 2013 1:49 am wrote:
> > > Klimax (danklima.delete@this.gmail.com) on July 11, 2013 12:28 am wrote:
> > > [...]
> > > > Are there any Java/Dalvik benchmarks for Android?
> > >
> > > Yes, and some are looking bad for Intel CT+.
> > >
> > > For instance for AndEBench Java the K900 (dual Saltwell + HT @ 2.0 GHz) gets 222 while A15 and
> > > Krait based Galaxy S4 get close to 600. And if you insist on dual core, Nexus 10 (dual A15) gets
> > > 379, while Samsung Galaxy Note (a device more than a year old, dual A9 @ 1.4GHz) gets 213.
> > >
> > > http://www.eembc.org/andebench/
> > >
> > > Of course that's a single point and no conclusion should be drawn on these results alone.
> > >
> > > > Anyway it is trivial to write bad benchmark. (And that's before
> > > > vendors get interested like with ScienceMark or AIDA...)
> > >
> > > And that's all that matters in the end: this particular benchmark has now been proven to heavily
> > > favor Intel, so it has become useless for comparing micro-architecture performance.
> > >
> > > I now wait for evidence that Geekbench favors ARM, and I somehow think
> > > nothing as obvious as what was found with AnTuTu will be uncovered.
> > >
> > So far:
> > http://forums.anandtech.com/showpost.php?p=35246412&postcount=13
> > from http://investorshub.advfn.com/boards/read_msg.aspx?message_id=88008447
> > Similar case as absence of NEON instructions. (Conservative or unusual compiler settings...)
> >
> > I'll run it through Intel VTune Amplifier and will see how it does. (Note that often dataset
> > from tool is in range of gigabytes of data) Only on 3930k, because I don't have currently
> > Atom PC online, but denormals IIRC are handled by microcode in precise situation.
>
> Similar as absence of NEON? Unless you show that the ARM version isn't
> also handling denormals this doesn't prove Geekbench favors ARM.
>
> I will save you some time: the x86 Android version uses SSE(2), not x87.
> Just look at the disassembly of _ZN10DotProduct12workerScalarEi
>
I don't follow. How disassembly tells us anything about denormals handling?
It's in control flags that we can't see.
> Now if you can also explain with denormals why CT+ is beaten by A15 and
> Krait even for single threaded integer tasks, I'm very interested :-)
>
It's beaten by the margin that one would expect:
http://browser.primatelabs.com/geekbench2/compare/2122693/1970335
http://browser.primatelabs.com/geekbench2/compare/2147177/1970335
The difference is probably very similar to the difference in power consumption. Which, of course, means that A15 and Krait are better CPUs since they got equal perf/Watt with higher absolute performance.
> Klimax (danklima.delete@this.gmail.com) on July 11, 2013 3:00 am wrote:
> > none (none.delete@this.none.com) on July 11, 2013 1:49 am wrote:
> > > Klimax (danklima.delete@this.gmail.com) on July 11, 2013 12:28 am wrote:
> > > [...]
> > > > Are there any Java/Dalvik benchmarks for Android?
> > >
> > > Yes, and some are looking bad for Intel CT+.
> > >
> > > For instance for AndEBench Java the K900 (dual Saltwell + HT @ 2.0 GHz) gets 222 while A15 and
> > > Krait based Galaxy S4 get close to 600. And if you insist on dual core, Nexus 10 (dual A15) gets
> > > 379, while Samsung Galaxy Note (a device more than a year old, dual A9 @ 1.4GHz) gets 213.
> > >
> > > http://www.eembc.org/andebench/
> > >
> > > Of course that's a single point and no conclusion should be drawn on these results alone.
> > >
> > > > Anyway it is trivial to write bad benchmark. (And that's before
> > > > vendors get interested like with ScienceMark or AIDA...)
> > >
> > > And that's all that matters in the end: this particular benchmark has now been proven to heavily
> > > favor Intel, so it has become useless for comparing micro-architecture performance.
> > >
> > > I now wait for evidence that Geekbench favors ARM, and I somehow think
> > > nothing as obvious as what was found with AnTuTu will be uncovered.
> > >
> > So far:
> > http://forums.anandtech.com/showpost.php?p=35246412&postcount=13
> > from http://investorshub.advfn.com/boards/read_msg.aspx?message_id=88008447
> > Similar case as absence of NEON instructions. (Conservative or unusual compiler settings...)
> >
> > I'll run it through Intel VTune Amplifier and will see how it does. (Note that often dataset
> > from tool is in range of gigabytes of data) Only on 3930k, because I don't have currently
> > Atom PC online, but denormals IIRC are handled by microcode in precise situation.
>
> Similar as absence of NEON? Unless you show that the ARM version isn't
> also handling denormals this doesn't prove Geekbench favors ARM.
>
> I will save you some time: the x86 Android version uses SSE(2), not x87.
> Just look at the disassembly of _ZN10DotProduct12workerScalarEi
>
I don't follow. How disassembly tells us anything about denormals handling?
It's in control flags that we can't see.
> Now if you can also explain with denormals why CT+ is beaten by A15 and
> Krait even for single threaded integer tasks, I'm very interested :-)
>
It's beaten by the margin that one would expect:
http://browser.primatelabs.com/geekbench2/compare/2122693/1970335
http://browser.primatelabs.com/geekbench2/compare/2147177/1970335
The difference is probably very similar to the difference in power consumption. Which, of course, means that A15 and Krait are better CPUs since they got equal perf/Watt with higher absolute performance.
