OCTA CORE PHONE VS QUAD CORE

It is usually very difficult to compare processors on just cores and GHz.  10 year old processors with 4 cores running at 2.5Ghz will be far slower than a modern quad core 2.5 GHz processor.  Things like improved branch prediction, improved CPU caches, better pipelining, etc. are making the difference, not the number of cores and clock speed.

The only way you can really tell is by benchmarks.                 
Quad core..although 8 cores will give you more functionality,like better multitasking, most apps are not built for use on more than 2-4 cores, which means they are usually unable to utilise the processors as efficiently as required.Also when you say 8 cores,all cores will not be running at any instance.
And in this case the octacore is clearly outstripped by the quad,since any advantage the octa has in terms of load sharing is matched by the superior speed of the quad.


ps.If this is what the question is realy about,the nexus 5 really beats the canvas knight on all counts except the battery.                                                               
If you do lots of parallel work (gaming and simultaneously running apps in background or for instance running 8 apps in background) then go for octa core 1.7 Ghz It will handle better.
If you want to get things done faster and would not do much multitasking (like running 4 apps in background) then go for 2.2Ghz quad core processor.

In short if the ram of you phone is less than or equal to 2gb then quad core.

And if the ram of your phone in more than 2 gb than octa core.  LIKE A GAMMING PERFORMANCE

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