Inside depgraph._merge_order_bias(), promote deep system runtime deps toward

the front of the merge list. This should help optimize merge order to account
for implicit system dependencies. (trunk r12710)

svn path=/main/branches/2.1.6/; revision=12965

diff --git a/pym/_emerge/__init__.py b/pym/_emerge/__init__.py
index 4c1c45e08f9368a0b0c2ca113f0e89a8cbe5a175..ede82cbf32e4e11b753bacf24e732984ec42b449 100644 (file)
--- a/pym/_emerge/__init__.py
+++ b/pym/_emerge/__init__.py
@@ -1104,6 +1104,38 @@ DepPrioritySatisfiedRange.ignore_priority = (
        DepPrioritySatisfiedRange._ignore_runtime
 )
 
+def _find_deep_system_runtime_deps(graph):
+       deep_system_deps = set()
+       node_stack = []
+       for node in graph:
+               if not isinstance(node, Package) or \
+                       node.operation == 'uninstall':
+                       continue
+               if node.root_config.sets['system'].findAtomForPackage(node):
+                       node_stack.append(node)
+
+       def ignore_priority(priority):
+               """
+               Ignore non-runtime priorities.
+               """
+               if isinstance(priority, DepPriority) and \
+                       (priority.runtime or priority.runtime_post):
+                       return False
+               return True
+
+       while node_stack:
+               node = node_stack.pop()
+               if node in deep_system_deps:
+                       continue
+               deep_system_deps.add(node)
+               for child in graph.child_nodes(node, ignore_priority=ignore_priority):
+                       if not isinstance(child, Package) or \
+                               child.operation == 'uninstall':
+                               continue
+                       node_stack.append(child)
+
+       return deep_system_deps
+
 class FakeVartree(portage.vartree):
        """This is implements an in-memory copy of a vartree instance that provides
        all the interfaces required for use by the depgraph.  The vardb is locked
@@ -6766,13 +6798,37 @@ class depgraph(object):
                return acceptable
 
        def _merge_order_bias(self, mygraph):
-               """Order nodes from highest to lowest overall reference count for
-               optimal leaf node selection."""
+               """
+               For optimal leaf node selection, promote deep system runtime deps and
+               order nodes from highest to lowest overall reference count.
+               """
+
                node_info = {}
                for node in mygraph.order:
                        node_info[node] = len(mygraph.parent_nodes(node))
+               deep_system_deps = (_find_deep_system_runtime_deps(mygraph))
+
                def cmp_merge_preference(node1, node2):
+
+                       if node1.operation == 'uninstall':
+                               if node2.operation == 'uninstall':
+                                       return 0
+                               return 1
+
+                       if node2.operation == 'uninstall':
+                               if node1.operation == 'uninstall':
+                                       return 0
+                               return -1
+
+                       node1_sys = node1 in deep_system_deps
+                       node2_sys = node2 in deep_system_deps
+                       if node1_sys != node2_sys:
+                               if node1_sys:
+                                       return -1
+                               return 1
+
                        return node_info[node2] - node_info[node1]
+
                mygraph.order.sort(key=cmp_sort_key(cmp_merge_preference))
 
        def altlist(self, reversed=False):
@@ -10132,38 +10188,10 @@ class Scheduler(PollScheduler):
                merged, these packages go to merge_wait_queue, to be merged when no
                other packages are building.
                """
-               graph = self._digraph
                deep_system_deps = self._deep_system_deps
                deep_system_deps.clear()
-               node_stack = []
-               for node in graph.order:
-                       if not isinstance(node, Package) or \
-                               node.operation == "uninstall":
-                               continue
-                       system_set = node.root_config.sets["system"]
-                       if system_set.findAtomForPackage(node):
-                               node_stack.append(node)
-
-               def ignore_priority(priority):
-                       """
-                       Ignore non-runtime priorities.
-                       """
-                       if isinstance(priority, DepPriority) and \
-                               (priority.runtime or priority.runtime_post):
-                               return False
-                       return True
-
-               while node_stack:
-                       node = node_stack.pop()
-                       if node in deep_system_deps:
-                               continue
-                       deep_system_deps.add(node)
-                       for child in graph.child_nodes(node, ignore_priority=ignore_priority):
-                               if not isinstance(child, Package) or \
-                                       child.operation == "uninstall":
-                                       continue
-                               node_stack.append(child)
-
+               deep_system_deps.update(
+                       _find_deep_system_runtime_deps(self._digraph))
                deep_system_deps.difference_update([pkg for pkg in \
                        deep_system_deps if pkg.operation != "merge"])