Managing multiple sources of page-hotness data

Knowing how frequently accessed a page of memory is (its "hotness") is a key input to many memory-management heuristics. Jonathan Cameron, in a memory-management track at the 2025 Linux Storage, Filesystem, Memory-Management, and BPF Summit, pointed out that the number of sources of that kind of data is growing over time. He wanted to explore the questions of what commonality exists between data from those sources, and whether it makes sense to aggregate them all somehow.
了解一页内存被访问的频率（即“热度”）是许多内存管理启发式算法中的关键输入。Jonathan Cameron 在 2025 年的 Linux 存储、文件系统、内存管理和 BPF 峰会的内存管理专题中指出，这类数据的来源正在不断增多。他希望探讨这些来源之间是否存在共通性，以及是否有意义以某种方式对它们进行聚合。

Cameron's own focus is on the CXL "hotness monitoring unit", which can provide detailed data on which pages in a CXL memory bank have been accessed, but there are many other data sources as well. He fears that it may be crazy to try to combine them all, but hopes that it makes sense to do so at least