Hacker News new | ask | show | jobs
by beebeepka 964 days ago
~100% of games don't fit into the L1 cache of a CPU.

It's the weekend, so I am just gonna say that a Ryzen 7800x3d has 512KB of L1 cache. Plenty of games would fit. Not even talking about those tiny games that generate everything.

2 comments

Despite the fact that AMD writes "512 kB" in its spec sheet, this number does not matter, because it multiplies the cache size with the number of cores.

The Ryzen 7000 CPUs have 32 kB of L1 instruction cache, 32 kB of L1 data cache and 1 MB of L2 cache per core, and 7800X3D also has 96 MB of L3 cache shared by the 8 cores.

These numbers determine at which cache level the data used by an execution thread can fit.

No modern game uses data that fits in the 32 kB of L1 data cache, and the game code also does not fit in the 32 kB instruction cache.

L1 cache isn’t shared between cores. One core in the 7800X3D only has 64k L1 cache.
Of the 64 kB L1 cache, only 32 kB is available for data.