By: juanrga (noemail.delete@this.juanrga.com), October 11, 2018 11:34 am
Room: Moderated Discussions
anon (spam.delete.delete@this.this.spam.com) on October 11, 2018 7:08 am wrote:
> juanrga (noemail.delete@this.juanrga.com) on October 11, 2018 3:11 am wrote:
> > nobody in particular (nobody.delete@this.nowhe.re) on October 10, 2018 8:55 am wrote:
> > > More info here
> > >
> > > "In essence, requests per second (RPS) per Watt is a critical metric that Qualcomm’s
> > > ARM64 46 core Falkor chip had a big advantage over Intel’s Skylake 4116. Embracing
> > > the value of optionality and market competition, we made some noise.
> > >
> > > Intel proposed to co-innovate with us an off-roadmap 24-core
> > > Xeon Gold CPU specifically made for our workload
> > > offering considerable value in Performance per Watt. For this generation, we continue using Intel as system
> > > solutions are widely available while we’re working on realizing ARM64’s benefits to production."
> > >
> > > Looks like Centriq was far less of a done deal for Cloudflare than many assumed.
> >
> > The blog claims custom Xeon "offering considerable value in Performance per Watt".
> >
> > Then adds that the custom Xeon increases "RPS by 200% from doubling the amount of cores" and increases
> > "the power consumption by 174% from increasing the CPUs TDP from 85W to 150W each".
> > Yes the number of cores is doubled, but the frequency drops
> > from 2.1GHz to 1.9GHz. So the RPS is only 181%, not "200%".
> >
> > So performance per watt is only 4% better, and far from the 2x gap offered by Falkor.
>
> If it's better at all.
>
> Cloudflare doesn't care about efficiency.
Ok, they can just claim that they care about density or that they got a rebate couldn't resist or whatever it is the reason, but then they could stop claiming that the custom Xeon is "offering considerable value in Performance per Watt" compared to the old Xeon.
> There is a reason why they
> had only one power consumption/efficiency test in their evaluation.
> They care about cost and density and they only care about density because it affects cost.
> Single socket 46 thread Falkor vs dual socket 48 thread Skylake is a win for Falkor.
> Similar performance, lower power consumption, lower cost per performance.
> Against dual socket 96 thread Skylake (at Xeon Gold prices) the density
> and system cost advantage is so large that efficiency becomes irrelevant.
> juanrga (noemail.delete@this.juanrga.com) on October 11, 2018 3:11 am wrote:
> > nobody in particular (nobody.delete@this.nowhe.re) on October 10, 2018 8:55 am wrote:
> > > More info here
> > >
> > > "In essence, requests per second (RPS) per Watt is a critical metric that Qualcomm’s
> > > ARM64 46 core Falkor chip had a big advantage over Intel’s Skylake 4116. Embracing
> > > the value of optionality and market competition, we made some noise.
> > >
> > > Intel proposed to co-innovate with us an off-roadmap 24-core
> > > Xeon Gold CPU specifically made for our workload
> > > offering considerable value in Performance per Watt. For this generation, we continue using Intel as system
> > > solutions are widely available while we’re working on realizing ARM64’s benefits to production."
> > >
> > > Looks like Centriq was far less of a done deal for Cloudflare than many assumed.
> >
> > The blog claims custom Xeon "offering considerable value in Performance per Watt".
> >
> > Then adds that the custom Xeon increases "RPS by 200% from doubling the amount of cores" and increases
> > "the power consumption by 174% from increasing the CPUs TDP from 85W to 150W each".
> > Yes the number of cores is doubled, but the frequency drops
> > from 2.1GHz to 1.9GHz. So the RPS is only 181%, not "200%".
> >
> > So performance per watt is only 4% better, and far from the 2x gap offered by Falkor.
>
> If it's better at all.
>
> Cloudflare doesn't care about efficiency.
Ok, they can just claim that they care about density or that they got a rebate couldn't resist or whatever it is the reason, but then they could stop claiming that the custom Xeon is "offering considerable value in Performance per Watt" compared to the old Xeon.
> There is a reason why they
> had only one power consumption/efficiency test in their evaluation.
> They care about cost and density and they only care about density because it affects cost.
> Single socket 46 thread Falkor vs dual socket 48 thread Skylake is a win for Falkor.
> Similar performance, lower power consumption, lower cost per performance.
> Against dual socket 96 thread Skylake (at Xeon Gold prices) the density
> and system cost advantage is so large that efficiency becomes irrelevant.