alt Hacker News> For the AMD 9950, we are talking about 1280kb of L1 (per core). 16MB of L2 (per core)
Ryzen 9 CPUs have 1280kB of L1 in total. 80kB (48+32) per core, and the 9 series is the first in the entire history of Ryzens to have some other number than 64 (32+32) kilobytes of L1 per core. The 16MB L2 figure is also total. 1MB per core, same as the 7 series. AMD obviously touts the total, not per-core, amounts in their marketing materials because it looks more impressive.
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kbolino • today at 4:24 PM
Also, rather importantly, the L1i (instruction) cache is still only 32 kB. The part that got bigger, the 48 kB of L1d (data) cache, does not count for this purpose.
Yeah, the reason for that is that it's expensive in PPA for the size of an L1 cache to exceed number of ways times page size. The jump to 48kB was also a jump to 12 way set associative.
As an aside, zen 1 did actually have a 64kB (and only 4 way!) L1I cache, but changed to the page size times way count restriction with zen 2, reducing the L1 size by half.
You can also see this on the apple side, where their giant 192kB caches L1I are 12 ways with a 16kB page size.