TechPowerUp – RUMOR: Intel "Raptor Lake" Rumored to Feature Massive Cache Size Increases
 
“Large on-die caches are expected to be a major contributor to IPC and gaming performance. The upcoming AMD Ryzen 7 5800X3D processor triples its on-die last-level cache using the 3D Vertical Cache technology, to level up to Intel's ‘Alder Lake-S’ processors in gaming, while using the existing ‘Zen 3’ IP. Intel realizes this, and is planning a massive increase in on-die cache sizes, although spread across the cache hierarchy. The next-generation ‘Raptor Lake-S’ desktop processor the company plans to launch in the second half of 2022 is rumored to feature 68 MB of ‘total cache’ (that's AMD lingo for L2 + L3 caches), according to a highly plausible theory by PC enthusiast OneRaichu on Twitter, and illustrated by Olrak29_.
 
The ‘Raptor Lake-S’ silicon is expected to feature eight ‘Raptor Cove’ P-cores, and four "Gracemont" E-core clusters (each cluster amounts to four cores). The ‘Raptor Cove’ core is expected to feature 2 MB of dedicated L2 cache, an increase over the 1.25 MB L2 cache per ‘Golden Cove" P-core of "Alder Lake-S.’ In a ‘Gracemont’ E-core cluster, four CPU cores share an L2 cache. Intel is looking to double this E-core cluster L2 cache size from 2 MB per cluster on ‘Alder Lake,’ to 4 MB per cluster. The shared L3 cache increases from 30 MB on ‘Alder Lake-S’ (C0 silicon), to 36 MB on ‘Raptor Lake-S.’ The L2 + L3 caches hence add up to 68 MB. All eyes are now on ‘Zen 4,’ and whether AMD gives the L2 caches an increase from the 512 KB per-core size that it's consistently maintained since the first ‘Zen.’ "
 
My thoughts:  The Raptor Lake rumors and leaks are going to start increasing in the next few months.  The 227%  increase of cache size on Raptor Lake is significant and I’m believe that Zen 4 will be comparable.