Some performance optimizations after analyzing benchmarks. (#5841)

* Some performance optimizations after analyzing benchmarks. 
* add news fragment

news/5841.bugfix.rst

@@ -0,0 +1 @@
+Add back some relevant caching to increase performance after the major refactor released with ``2023.8.19``

pipenv/resolver.py

@@ -3,6 +3,11 @@
 import os
 import sys
 
+try:
+    from functools import cached_property
+except ImportError:
+    cached_property = property
+
 
 def _ensure_modules():
     spec = importlib.util.spec_from_file_location(
@@ -226,6 +231,7 @@ def marker_to_str(marker):
             return marker_str
         return None
 
+    @cached_property
     def get_cleaned_dict(self):
         self.validate_constraints()
         if self.entry.extras != self.lockfile_entry.extras:
@@ -550,7 +556,7 @@ def clean_results(results, resolver, project, category):
             reverse_deps=reverse_deps,
             category=category,
         )
-        entry_dict = translate_markers(entry.get_cleaned_dict())
+        entry_dict = translate_markers(entry.get_cleaned_dict)
         new_results.append(entry_dict)
     return new_results
 

pipenv/utils/resolver.py

@@ -326,19 +326,24 @@ def prepare_index_lookup(self):
                 alt_index_lookup[req_name] = index_mapping[index]
         return alt_index_lookup
 
-    @property
-    def finder(self):
+    @cached_property
+    def package_finder(self):
         finder = get_package_finder(
             install_cmd=self.pip_command,
             options=self.pip_options,
             session=self.session,
         )
+        return finder
+
+    @property
+    def finder(self):
+        finder = self.package_finder
         index_lookup = self.prepare_index_lookup()
         finder._link_collector.index_lookup = index_lookup
         finder._link_collector.search_scope.index_lookup = index_lookup
         return finder
 
-    @property
+    @cached_property
     def parsed_constraints(self):
         pip_options = self.pip_options
         pip_options.extra_index_urls = []
@@ -434,9 +439,10 @@ def get_resolver(self, clear=False):
             yield resolver
 
     def resolve(self):
+        constraints = self.constraints
         with temp_environ(), self.get_resolver() as resolver:
             try:
-                results = resolver.resolve(self.constraints, check_supported_wheels=False)
+                results = resolver.resolve(constraints, check_supported_wheels=False)
             except InstallationError as e:
                 raise ResolutionFailure(message=str(e))
             else:
@@ -512,6 +518,7 @@ def collect_hashes(self, ireq):
             return {self.project.get_hash_from_link(self.hash_cache, link)}
         return set()
 
+    @cached_property
     def resolve_hashes(self):
         if self.results is not None:
             for ireq in self.results:
@@ -612,7 +619,7 @@ def actually_resolve_deps(
             category,
         )
         resolver.resolve()
-        hashes = resolver.resolve_hashes()
+        hashes = resolver.resolve_hashes
         resolver.resolve_constraints()
         results = resolver.clean_results()
     for warning in warning_list: