By: Ricardo B (ricardo.b.delete@this.xxxxxx.xx), May 19, 2013 7:20 am
Room: Moderated Discussions
tianbing (tianbing1212.delete@this.gmail.com) on May 18, 2013 9:08 pm wrote:
> A few years ago, they told me that OOO parts consume lots of energy,
> so they gave it up in Atom to achieve low power consumption.
> But now, you say, the OOO get better performance power ratio compared with MT.
> Who can explain it...
It mostly depends on where in the single threaded power/performance curve the design is aiming for.
If you're aiming for low performance, a simple design will yield the best power efficiency.
But you're aiming at high performance, you need to use OoO to get there and make good use of the execution logic, caches, etc.
> A few years ago, they told me that OOO parts consume lots of energy,
> so they gave it up in Atom to achieve low power consumption.
> But now, you say, the OOO get better performance power ratio compared with MT.
> Who can explain it...
It mostly depends on where in the single threaded power/performance curve the design is aiming for.
If you're aiming for low performance, a simple design will yield the best power efficiency.
But you're aiming at high performance, you need to use OoO to get there and make good use of the execution logic, caches, etc.