Bug #228977 - During dblink._preserve_libs() calls, cache results of

LinkageMap.findProviders(), LinkageMap.findConsumers(), and os.path.realpath()
calls in order to improve performance. This makes a huge difference in
performance for glibc upgrades since glibc provides so many libs to
check consumerge for.

svn path=/main/trunk/; revision=10764

diff --git a/pym/portage/dbapi/vartree.py b/pym/portage/dbapi/vartree.py
index f71a207940c572fab2e7798491b1d4afb42f1b01..8358927221857e5c87dd133c390680bbf7dfa5ca 100644 (file)
--- a/pym/portage/dbapi/vartree.py
+++ b/pym/portage/dbapi/vartree.py
@@ -201,30 +201,48 @@ class LinkageMap(object):
        def findProviders(self, obj):
                if not self._libs:
                        self.rebuild()
+
+               realpath_cache = {}
+               def realpath(p):
+                       real_path = realpath_cache.get(p)
+                       if real_path is None:
+                               real_path = os.path.realpath(p)
+                               realpath_cache[p] = real_path
+                       return real_path
+
                rValue = {}
                if obj not in self._obj_properties:
-                       obj = os.path.realpath(obj)
+                       obj = realpath(obj)
                        if obj not in self._obj_properties:
                                raise KeyError("%s not in object list" % obj)
                arch, needed, path, soname = self._obj_properties[obj]
                path.extend(self._defpath)
-               path = [os.path.realpath(x) for x in path]
+               path = set(realpath(x) for x in path)
                for x in needed:
                        rValue[x] = set()
                        if x not in self._libs or arch not in self._libs[x]:
                                continue
                        for y in self._libs[x][arch]["providers"]:
-                               if x[0] == os.sep and os.path.realpath(x) == os.path.realpath(y):
+                               if x[0] == os.sep and realpath(x) == realpath(y):
                                        rValue[x].add(y)
-                               elif os.path.realpath(os.path.dirname(y)) in path:
+                               elif realpath(os.path.dirname(y)) in path:
                                        rValue[x].add(y)
                return rValue
        
        def findConsumers(self, obj):
                if not self._libs:
                        self.rebuild()
+
+               realpath_cache = {}
+               def realpath(p):
+                       real_path = realpath_cache.get(p)
+                       if real_path is None:
+                               real_path = os.path.realpath(p)
+                               realpath_cache[p] = real_path
+                       return real_path
+
                if obj not in self._obj_properties:
-                       obj = os.path.realpath(obj)
+                       obj = realpath(obj)
                        if obj not in self._obj_properties:
                                raise KeyError("%s not in object list" % obj)
                rValue = set()
@@ -233,10 +251,10 @@ class LinkageMap(object):
                                if obj in self._libs[soname][arch]["providers"]:
                                        for x in self._libs[soname][arch]["consumers"]:
                                                path = self._obj_properties[x][2]
-                                               path = [os.path.realpath(y) for y in path+self._defpath]
-                                               if soname[0] == os.sep and os.path.realpath(soname) == os.path.realpath(obj):
+                                               path = [realpath(y) for y in path+self._defpath]
+                                               if soname[0] == os.sep and realpath(soname) == realpath(obj):
                                                        rValue.add(x)
-                                               elif os.path.realpath(os.path.dirname(obj)) in path:
+                                               elif realpath(os.path.dirname(obj)) in path:
                                                        rValue.add(x)
                return rValue
                                        
@@ -1995,9 +2013,15 @@ class dblink(object):
                        if os.path.islink(x) and os.path.realpath(x) in candidates and x not in mycontents:
                                candidates.add(x)
 
+               provider_cache = {}
+               consumer_cache = {}
+
                # ignore any libs that are only internally used by the package
                def has_external_consumers(lib, contents, otherlibs):
-                       consumers = linkmap.findConsumers(lib)
+                       consumers = consumer_cache.get(lib)
+                       if consumers is None:
+                               consumers = linkmap.findConsumers(lib)
+                               consumer_cache[lib] = consumers
                        contents_without_libs = [x for x in contents if x not in otherlibs]
                        
                        # just used by objects that will be autocleaned
@@ -2024,10 +2048,19 @@ class dblink(object):
                                continue
                        # only preserve the lib if there is no other copy to use for each consumer
                        keep = False
-                       for c in linkmap.findConsumers(lib):
+
+                       lib_consumers = consumer_cache.get(lib)
+                       if lib_consumers is None:
+                               lib_consumers = linkmap.findConsumers(lib)
+                               consumer_cache[lib] = lib_consumers
+
+                       for c in lib_consumers:
                                localkeep = True
-                               providers = linkmap.findProviders(c)
-                               
+                               providers = provider_cache.get(c)
+                               if providers is None:
+                                       providers = linkmap.findProviders(c)
+                                       provider_cache[c] = providers
+
                                for soname in providers:
                                        if lib in providers[soname]:
                                                for p in providers[soname]: