Looking at Loongsons processors for instance. About 15 years ago they coudl barely compete with a Pentium 2. Now they are about 4-5 years behind Intel/AMD. Further behind on some more specific work loads (SSL decoding for example) Not great but that is a decent jump. The jumps between generations are pretty decent.
LA446 was a decent enough processor core but had an awful memory controller that held it back as soon as it needed to reach outside of cache. As such it was SLOW.
But they learned the lesson and now the LA664 almost entirely fixed that issue. I think a big part of performance issues is that they are working domestic 5 to 7nm processes, so a good 5-7 years behind.
They are launching the LA864 later this year and are touting some decent performance gains. That is just marketing so far but something to keep an eye on.
Considering that these chips are using their own ISA, own designs, domestic manufacturing and they aren't terrible is a big thing.
I suspect in the next 5 years they have the chance of completely closing the gap. But it can also go the other way that they end up stalling as smaller nodes get much more difficult to attain.
