Intel Meteor Lake 14th Gen Will Bring Big Architectural Changes For Efficiency Cores

Intel's processors include hardware to help with monitoring their own performance. Unsurprisingly, these are known as "Performance Monitoring Units" (PMU). The company releases JSON files that map the raw data provided by the PMUs to human-readable events and has already released one for its 14th-generation Meteor Lake processors. From reading those, the Coelacanth has figured out that Meteor Lake's Crestmont cores will be a significant change from the Gracemont cores used in Alder Lake and Raptor Lake.

Over in the Perfmon directory at Intel's 01 open source website, we can find an "MTL" folder, and in that folder you can find a couple of JSON files that are named meteorlake_crestmont_core and meteorlake_redwoodcove_core. The names of the cores aren't anything new; we first heard about Redwood Cove back in 2020.

Alder Lake incremented both numbers by one with its revised Golden Cove and Gracemont cores, the former being the P-core architecture and the latter being the E-core architecture. According to the perfmon JSON files, neither Raptor Lake nor Meteor Lake will increment the Native Model ID for their P-cores. That can be interpreted as meaning that both Raptor Cove and Redwood Cove are minor revisions on ADL's Golden Cove.
Arguably the more interesting news is that Redwood Cove could be another revision of the Golden Cove architecture. Way back in May, leaker Raichu (@OneRaichu on Twitter) noted that Redwood Cove will focus on efficiency improvements at every level, including the core architecture. This is likely because the Intel 4 process that Meteor Lake will be using can't reach the same insane clock rates that Intel's mature "Intel 7" process can. More recently, fellow leakers @harukaze5719 and @9550pro had the same discussion after the Coelacanth's post above.