The page cache is one directory per document; the shipped suites measure under a UTF-8 locale (from dev 3321e7c9e36e)

sks/document/document_class.h

@@ -193,7 +193,10 @@ public:
     std::vector<std::pair<std::string, std::string>> m_string_components {};
     std::vector<std::tuple<std::string,std::string,std::string,std::string>> m_toc_components {};
 
+    // The page cache of THIS document under a target's cache directory
+    // (document_class.cpp); set by each target's create_*_output_directories().
     std::string m_cache_dir {};
+    std::string document_cache_directory(const std::string& target_cache) const;
 };
 
 fs::path parse_input_filename(const std::string& s, const std::string& input_dir);