Intel's Lion Cove P-Core and Gaming Workloads

Summary

Lion Cove is Intel’s latest high performance CPU architecture. Compared to its predecessor, Raptor Cove, Intel’s newest core can sustain more instructions per cycle, reorganizes the execution engine, and adds an extra level to the data cache hierarchy. The list of changes goes on, with tweaks to just about every part of the core pipeline. Lion Cove does well in the standard SPEC CPU2017 benchmark suite, where it posts sizeable gains especially in higher IPC subtests. In the Arrow Lake desktop platform, Lion Cove can often go head-to-head against AMD’s Zen 5, and posts an overall lead over Intel’s prior Raptor Cove while pulling less power. But a lot of enthusiasts are interested in gaming performance, and games have different demands from productivity workloads.Here, I’ll be running a few games while collecting performance monitoring data. I’m using the Core Ultra 9 285K with DDR5-6000 28-36-36-96, which is the fastest memory I have available. E-Cores are turned off in the BIOS, because setting affinity to P-Cores caused massive stuttering in Call of Duty. In Cyberpunk 2077, I’m using the built-in benchmark at 1080P and medium settings, with upscaling turned off. In Palworld, I’m hanging out near a base, because CPU load tends to be higher with more entities around.Gaming workloads generally fall at the low end of the IPC range. Lion Cove can sustain eight micro-ops per cycle, which roughly corresponds to eight instructions per cycle because most instructions map to a single micro-op. It posts very high IPC figures in several SPEC CPU2017 tests, with some pushing well past 4 IPC. Games however get nowhere near that, and find company with lower IPC tests that see their performance limited by frontend and backend latency.Top-down analysis characterizes how well an application is utilizing a CPU core’s width, and accounts for why pipeline slots go under-utilized. This is usually done at the rename/allocate stage, because it’s often the narrowest stage in the core’s pip...