diff --git a/bitbake/lib/bb/cooker.py b/bitbake/lib/bb/cooker.py
index 1124332186..a05630d52d 100644
--- a/bitbake/lib/bb/cooker.py
+++ b/bitbake/lib/bb/cooker.py
@@ -1940,7 +1940,8 @@ class Parser(multiprocessing.Process):
                 except IndexError:
                     break
                 result = self.parse(*job)
-
+                # Clear the siggen cache after parsing to control memory usage, its huge
+                bb.parse.siggen.postparsing_clean_cache()
             try:
                 self.results.put(result, timeout=0.25)
             except queue.Full:
diff --git a/bitbake/lib/bb/siggen.py b/bitbake/lib/bb/siggen.py
index ffd8fcaf36..c2d0c736cf 100644
--- a/bitbake/lib/bb/siggen.py
+++ b/bitbake/lib/bb/siggen.py
@@ -51,6 +51,9 @@ class SignatureGenerator(object):
     def finalise(self, fn, d, varient):
         return
 
+    def postparsing_clean_cache(self):
+        return
+
     def get_unihash(self, tid):
         return self.taskhash[tid]
 
@@ -188,6 +191,14 @@ class SignatureGeneratorBasic(SignatureGenerator):
         for task in taskdeps:
             d.setVar("BB_BASEHASH_task-%s" % task, self.basehash[fn + ":" + task])
 
+    def postparsing_clean_cache(self):
+        #
+        # After parsing we can remove some things from memory to reduce our memory footprint
+        #
+        self.gendeps = {}
+        self.lookupcache = {}
+        self.taskdeps = {}
+
     def rundep_check(self, fn, recipename, task, dep, depname, dataCache):
         # Return True if we should keep the dependency, False to drop it
         # We only manipulate the dependencies for packages not in the whitelist