diff --git a/tools/profile_analyzer/profile_analyzer.py b/tools/profile_analyzer/profile_analyzer.py
index 074ceb8428d..8db0b68f89e 100755
--- a/tools/profile_analyzer/profile_analyzer.py
+++ b/tools/profile_analyzer/profile_analyzer.py
@@ -1,14 +1,110 @@
 #!/usr/bin/env python2.7
 import json
 import collections
+import itertools
+
+
+SELF_TIME = object()
+TIME_FROM_SCOPE_START = object()
+TIME_TO_SCOPE_END = object()
+TIME_FROM_STACK_START = object()
+TIME_TO_STACK_END = object()
+
+
+class LineItem(object):
+
+	def __init__(self, line, indent):
+		self.tag = line['tag']
+		self.indent = indent
+		self.time_stamp = line['t']
+		self.important = line['type'] == '!'
+		self.times = {}
+
+
+class ScopeBuilder(object):
+
+	def __init__(self, call_stack_builder, line):
+		self.call_stack_builder = call_stack_builder
+		self.indent = len(call_stack_builder.stk)
+		self.top_line = LineItem(line, self.indent)
+		call_stack_builder.lines.append(self.top_line)
+		self.first_child_pos = len(call_stack_builder.lines)
+
+	def mark(self, line):
+		pass
+
+	def finish(self, line):
+		assert line['tag'] == self.top_line.tag
+		final_time_stamp = line['t']
+		assert SELF_TIME not in self.top_line.times
+		self.top_line.tims[SELF_TIME] = final_time_stamp - self.top_line.time_stamp
+		for line in self.call_stack_builder.lines[self.first_child_pos:]:
+			if TIME_FROM_SCOPE_START not in line.times:
+				line[TIME_FROM_SCOPE_START] = line.time_stamp - self.top_line.time_stamp
+				line[TIME_TO_SCOPE_END] = final_time_stamp - line.time_stamp
+
+
+class CallStackBuilder(object):
+	
+	def __init__(self):
+		self.stk = []
+		self.signature = ''
+		self.lines = []
+
+	def add(self, line):
+		line_type = line['type']
+		self.signature = '%s%s%s' % (self.signature, line_type, line['tag'])
+		if line_type == '{':
+			self.stk.append(ScopeBuilder(self, line))
+			return False
+		elif line_type == '}':
+			self.stk.pop().finish(line)
+			return not self.stk
+		elif line_type == '.' or line_type == '!':
+			self.stk[-1].mark(line, True)
+			return False
+		else:
+			raise Exception('Unknown line type: \'%s\'' % line_type)
+
+
+class CallStack(object):
+
+	def __init__(self, initial_call_stack_builder):
+		self.count = 1
+		self.signature = initial_call_stack_builder.signature
+		self.lines = initial_call_stack_builder.lines
+		for line in lines:
+			for key, val in line.times.items():
+				line.times[key] = [val]
+
+	def add(self, call_stack_builder):
+		assert self.signature == call_stack_builder.signature
+		self.count += 1
+		assert len(self.lines) == len(call_stack_builder.lines)
+		for lsum, line in itertools.izip(self.lines, call_stack_builder.lines):
+			assert lsum.tag == line.tag
+			assert lsum.times.keys() == line.times.keys()
+			for k, lst in lsum.times.iterkeys():
+				lst.append(line.times[k])
+
+
+builder = collections.defaultdict(CallStackBuilder)
+call_stacks = collections.defaultdict(CallStack)
 
-data = collections.defaultdict(list)
 with open('latency_trace.txt') as f:
   for line in f:
     inf = json.loads(line)
     thd = inf['thd']
-    del inf['thd']
-    data[thd].append(inf)
+    cs = builder[thd]
+    if cs.add(inf):
+    	if cs.signature in call_stacks:
+    		call_stacks[cs.signature].add(cs)
+    	else:
+    		call_stacks[cs.signature] = CallStack(cs)
+    	del builder[thd]
 
-print data
+call_stacks = sorted(call_stacks.values(), key=lambda cs: cs.count, reverse=True)
 
+for cs in call_stacks:
+	print cs.signature
+	print cs.count