-1

Top500 says that Summit has 2,414,592 cores: https://www.top500.org/system/179397. But they have 4608 nodes, 9216 chips (each node has 2 chips), and 22 cores per chip. This is 202,752 cores. Where exactly does the number 2,414,592 come from?

Likewise, the webpage of Sierra clearly says that there's 190,080 cores: https://computation.llnl.gov/computers/sierra. But top500 says they have over 1 million.

This is my first question here, so please accept my apologies if this is not a "server" question. I have asked on Meta where to ask HPC questions: https://meta.stackexchange.com/questions/327714/where-should-hpc-questions-about-schedulers-go-stackoverflow-superuser-comput, but there is not yet a stack exchange just for HPC.

user1271772
  • 101
  • 4

1 Answers1

2

Validate the number with a rough order of magnitude estimate. 20 two socket servers in a rack, 20 CPU cores per socket. 300 racks is enormous for one computer, that's many MW of power draw. So, in excess of 200,000 CPU cores is possible.

GPU streaming multiprocessors also count as cores, at least to Linpack. The Next Platform peeled the covers off the Summit supercomputer:

The Power9 chips used in Summit have 22 cores running at 3.1 GHz, and there are a pair of them in each node for a total of 202,752 cores across those 4,608 nodes. There are six Volta GPU accelerators on the machine, for a total of 2.21 million SMs. Add it all up, and there are 2.41 million “cores” as the Linpack folk count them in the Summit machine.

Gone are the days when one simple multiplication will get you the performance of a machine.

John Mahowald
  • 32,050
  • 2
  • 19
  • 34