Re: buying a new computer
Posted: Mon Aug 19, 2019 5:47 pm
What does I/O and memory channel mean? How does it benefit chess engines?
Very good news.jpqy wrote: ↑Sun Aug 18, 2019 12:12 pm AMD 3rd Gen Ryzen Threadripper ‘Sharkstooth’ With 32 Zen 2 Cores Possibly Spotted in Geekbench – Up To 35% Faster Than Ryzen Threadripper 2990WX
https://wccftech.com/amd-ryzen-threadri ... u-spotted/
JP.
More memory channels means that more data can travel between CPU and RAM in a given amount of time. So, for chess engines, reading information from the hash table becomes faster, for example.
I/O is the number of PCIe connections to the CPU. Each PCIe 3.0 "lane" connection supports 985 MB/s to... well... anything. Ethernet, GPUs, NVMe SSDs, etc. etc. On modern computers, you use x2 or x4 connections to SSDs (1.9GB/s and 3.9GB/s respectively), and x8 or x16 connections to GPUs (15.7GB/s). The M.2 slots usually use x4 connections.
RLDRAM3 is the last version, and nothing else seems announced. I don't think there are many opportunities for latency to be further reduced in the future.Raphexon wrote: ↑Mon Aug 19, 2019 8:18 pmL3 caches of 1gb thanks to RLDRAM in future will be crazy.
Maybe you should buy an Intel 8 CPU 8280M system or the "NEW AND IMPROVED" 8 CPU 9200 based system!Joost Buijs wrote: ↑Mon Aug 19, 2019 4:10 pmZenmastur wrote: ↑Mon Aug 19, 2019 12:03 pmThey have full AVX2 support and all data paths and EU's are now 256-bit. So, AVX2 shouldn't be "slow" on the new CPU's. AVX2 performance is on par with all intel CPU's EVEN when executing highly optimized Intel code. No AVX-512 support that I'm aware of.Joost Buijs wrote: ↑Mon Aug 19, 2019 6:44 amIndeed, it looks like they didn't fix it. I don't need it for computer chess per se, but I'm also doing cryptography and in a new chess engine I'm working on I make heavy use of PEXT() in the evaluation function.jpqy wrote: ↑Sun Aug 18, 2019 8:04 pm Ipman has benches with the new AMD Ryzen R9 3900X
and BMI2 is still clearly slower then pop version on AMD cpu's..
http://www.ipmanchess.yolasite.com/amd- ... -bench.php
JP.
AMD also has slow AVX2, no AVX512 and no BF16 like the upcoming Intel 'Cooper Lake' chips. If you just use the machine to run Stockfish or any other chess engine it probably doesn't matter, but if you like to program and experiment with new algorithms it could be a drawback.
Regards,
Zenmastur
Benchmarks show the same AVX2 performance because they compare 56 Intel cores with 128 AMD cores, so that is not really on par. AMD gives you a lot of cores for the money, but Intel still has the higher performance when you do the comparison with an equal number of cores.
AVX is WAY to important to fall under that umbrella!