[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Date: Mon, 22 Dec 2014 22:57:21 +0100
From: marcel@...wthinkers.net
To: john-users@...ts.openwall.com
Subject: Re: ARM exynos 5410 benchmark results
In message <20141222203619.GA29434@...nwall.com>, Solar Designer writes:
> > supposedly a 5V 2A supply will not work. This is something I have not
> > tested.
>
> You'd need to measure the current before you test this, or you'd likely
> burn the 2A PSU.
I think I'll pass. There was a version of the board made that had
power analysis built in (Odroid XU+E), finding someone with one of
those would probably be easier.
> > > I think you wrongly stated that you ran 8 threads. I think you
> > > only ran 4. If so, please correct that little detail.
> >
> > Checked, and I did fill it out correctly. Total cores is 8 for this
> > SoC, it's big.LITTLE. 4 x Cortex-a7 which can switch to 4 x Cortex-A15.
> >
> > So total cores turns out to be 8, with only 4 being active at
> > any one time.
>
> Oh, I didn't realize you specified "4 / 8" rather than "8 / 4" (like we
> would for a more typical system with multiple logical CPUs per core).
> That's not how this notation was meant to be used, but it's a curious
> extension we could consider for cases such as yours. I think it'd get
> very confusing and ambiguous when those CPUs also start supporting
> multiple threads per core, though. For example, what if your chip
> supported 2 threads/core? Would you specify "8 / 8", because you'd run
> 8 threads on 4 cores, and have another 4 cores idle (which would in fact
> be the optimal way to use that chip)? But people would surely read this
> as 8 threads running on 8 cores! So let's not go for those extensions.
> I'll fix your entry to "4 / 4" now, because for our purposes the chip
> has 4 cores.
Fair enough, but keep in mind that things are about to get a lot more
complicated. Have a look at
https://www.linaro.org/blog/hardware-update/big-little-software-update/
for some of the things that are coming.
Add to that the eventual (?) release of working OpenCL libs for these
devices.
- marcel
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
