128-core AMD server

[noobpwnftw]

I have a couple of Supermicro boxes that are 4/8 way Xeons.

1. Yes, you can run Windows.
2. Large memory allocation is transparent and far-side NUMA latency is not significant.
3. Most chess engines doesn't spread threads properly across Processor Groups when you have more than 64 cores, including SF.
4. You will almost always want more cores, <= 1TB memory usage of Xiangqi EGTBs takes about 3 years to build on 4x4669v4 running 24/7.
5. HT gives about 30% overall NPS increase but can cause ELO drop due to poor performance on logical cores.

[Dann Corbit]

Can you allocate all 128 cores to 1 task? Mine got here early, but I am going to have to buy a couple of cables at Frys to get it set up

[jdart]

Can you allocate all 128 cores to 1 task?

Nope. As I said, it is basically four dual-CPU computers in one chassis, each with 32 cores.

--Jon

[Leo]

I bought the other one.

I believe that this settles the question of who sends the most money on electricity for computer chess.

Lol. Pretty much.

[Leo]

Some benchmarks (Stockfish 8, 16G hash):

32-core dual Opteron (2xOpteron 6376, 1/4 of the AMD server box, Linux):
26.3M nps

24-core dual Opteron (2xOpteron 6344, Linux):
21.8M nps

dual Xeon 2670 (16 cores, Linux):
24.0M nps

i7-6900k (8 cores, Windows):
14.08M nps

What about the argument that its time to depth that matters?

[Leo]

Rates in my area ramp up with usage and I have once in a while hit their "super overcharge now we're really serious" rate level, whatever they actually call it.

I am planning to get solar panels on the house next year.

--Jon

I have a 15 amp breaker that kept tripping. It was hot to the touch. I now have to wait until I can hook up the computer to 20 amps.

[jhellis3]

What about the argument that its time to depth that matters?

TTD is a useless measurement for LazySMP.

[Adam Hair]

Rates in my area ramp up with usage and I have once in a while hit their "super overcharge now we're really serious" rate level, whatever they actually call it.

I am planning to get solar panels on the house next year.

--Jon

I have a 15 amp breaker that kept tripping. It was hot to the touch. I now have to wait until I can hook up the computer to 20 amps.

Have your electrician check for a loose connection also. There could be a problem where the wire connects to the circuit breaker (small possibility) or where the circuit breaker plugs onto the electrical panel busbar (greater possibility). It is doubtful that you have a large enough overcurrent to cause the circuit breaker to be hot to the touch.

My guess is that the connection between the breaker and busbar is failing.

[Leo]

I have read over and over that a powerful 8-16 core machine will defeat a 32-64 core machine. After 16 to 20 cores it scales very badly. Has something changed or is this still true?

[Leo]

Rates in my area ramp up with usage and I have once in a while hit their "super overcharge now we're really serious" rate level, whatever they actually call it.

I am planning to get solar panels on the house next year.

--Jon

I have a 15 amp breaker that kept tripping. It was hot to the touch. I now have to wait until I can hook up the computer to 20 amps.

Have your electrician check for a loose connection also. There could be a problem where the wire connects to the circuit breaker (small possibility) or where the circuit breaker plugs onto the electrical panel busbar (greater possibility). It is doubtful that you have a large enough overcurrent to cause the circuit breaker to be hot to the touch.

My guess is that the connection between the breaker and busbar is failing.

Thanks for the info.