trn
Posts: 46
Joined: Wed May 09, 2012 11:30 am

Rpi vs A8, cpu compare

Sat Jul 07, 2012 12:27 pm

In %, how much is A8 at 1.5Ghz better vs rpi on 700Mhz?

kadamski
Posts: 187
Joined: Fri Jun 08, 2012 10:56 pm

Re: Rpi vs A8, cpu compare

Sun Jul 08, 2012 9:37 pm

It depends on a workload. It will be probably about 3-4 times faster on general computation. Cortex-A8 has 2 DMIPS/Mhz while ARM11 has 1.25 DMIPS/Mhz, Cortex-A8 has NEON, usually has bigger caches, better branch prediction. I've seen some cases where floating point operations where slower on Cortex processors, though (VFP is optional there).

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AndrewS
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Re: Rpi vs A8, cpu compare

Thu Jul 12, 2012 12:26 am

...and if you're running a particularly memory-intensive program, your Cortex-A8 may be attached to much more memory than the 256MB available to the Raspi.
...and if you're running a particularly disk-intensive program, your A8 might be connected to a chipset containing a SATA controller, much better than the flaky USB-driver used by the Raspi.
...and if you're running a particularly network-intensive program, your A8 might be connected to a chipset containing a gigabit ethernet controller, much better than the USB-ethernet used by the Raspi.
...and if you're running a particularly graphics-intensive program, your A8 is unlikely to have something as fast as the VideoCore IV used by the Raspi :D

etc. etc. ;)

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