4 ms·
No, they don't. Memory latencies for top-end phones like the iPhone are generally over 100 ns, which far from being a huge advantage is consderably worse than t
by BeeOnRope 6y ago
No, they don't. Memory latencies for top-end phones like the iPhone are generally over 100 ns, which far from being a huge advantage is consderably worse than the best desktop and latpop x86 chip latencies which hover around 50 ns.
- Retric 6y agoYou’re numbers are way off, where did you get them? Ex: https://en.wikipedia.org/wiki/CAS_latency https://en.wikipedia.org/wiki/CAS_latency
- BeeOnRope 6y agoBenchmarks. CAS latency is only a small part of total memory latency as seen by the CPU.
- Retric 6y agoAs we are talking about comparing different CPU architectures it’s the external latency that’s important. Even then I have been looking at sub 25ns on AMD CPU memory benchmarks and I assume similar Intel numbers.
- sliken 6y agoI generally try to quantify TLB latency and DRAM latency separately. The M1 chip has quite impressive memory latency around 30ns, assuming you aren't thrashing the TLB. Desktops tend to be much higher latency, like say the AMD ryzen 5950X. In particular the R per RV range benchmark uses between 1 and 32 pages in a sliding window. The M1 gets around 30ns (which I've personally verified with code I wrote) and the Ryzen 5950x gets around 65ns. Intel does a bit better than AMD, but nowhere close to the M1.