The new ranking of the most powerful supercomputers in the world was published on June 22 (https://top500.org/lists/top500/2020/06/). The first place is taken by the Japanese supercomputer Fugaku, located at the Riken Center for Computational Science in Japan. Fugaku has 7,299,072 processor cores and performs 415.5 quadrillion operations per second. Top 3 is complemented by the second-ranked supercomputer Summit, located in the United States, which has 2,414,592 processor cores, operations per second are 148.8 quadrillion. In third place is Sierra, also a US-based supercomputer, with estimates of up to 94.6 quadrillion operations per second. The list of the 10 most powerful supercomputers includes 5 supercomputers from the USA, 2 from China, 1 from Italy and 1 from Switzerland.
In the first place for the most energy efficient system of Green500 is ranked MN-3, based on a new server. He set a record of 21.1 gigaflops per watt while performing 1.62 petaflops. The system derives its superior energy efficiency from the MN-Core chip, an accelerator optimized for matrix arithmetic. It is ranked number 395 in the TOP500 list. More information on the various rankings can be found here.
More complete information: https://top500.org/
You can read more about the Riken project and the Fugaku supercomputer here.