Add memory analysis script

test/meminfo.py

@@ -0,0 +1,128 @@
+#!/usr/bin/env python2
+
+import argparse
+import sys
+
+
+# Returns true if `value` is an integer represented as a string.
+def is_int(value):
+  # type: (str) -> bool
+  try:
+    value = int(value)
+  except ValueError:
+    return False
+  return True
+
+
+def get_mappings(pid):
+  mappings = []
+  with open("/proc/{0}/smaps".format(pid)) as f:
+    mapping = None
+    for line in f:
+      if ": " not in line:
+        # Header
+        # 00400000-00447000 r-xp 00000000 fd:00 11667056     /usr/bin/tint2
+        if mapping:
+          mappings.append(mapping)
+        mapping = {}
+        mapping["path"] = line.strip().split("  ", 1)[-1].strip()
+      elif mapping:
+        # Entry
+        # Size:                  4 kB
+        # VmFlags: rd mr mw me dw ac sd
+        key, val = [s.strip() for s in line.split(":", 1)]
+        if val.endswith(" kB") and is_int(val.split(" kB", 1)[0]):
+          val = int(val.split(" kB", 1)[0]) * 1024
+        mapping[key] = val
+      else:
+        print "Cannot handle line:", line
+        raise RuntimeException("Parsing error")
+  if mapping:
+    mappings.append(mapping)
+  return mappings
+
+
+def extract_mappings(maps, select_func, group_func):
+  parts = {}
+  for m in maps:
+    if "Rss" in m and is_int(m["Rss"]) and m["Rss"] > 0 and select_func(m):
+      group = group_func(m)
+      if group not in parts:
+        parts[group] = 0
+      parts[group] += m["Rss"]
+  parts = parts.items()
+  parts.sort(key=lambda p: -p[1])
+  total = sum([p[1] for p in parts])
+  return total, parts
+
+
+def print_histogram(name, maps, extractor_func, detailed):
+  total, histogram = extractor_func(maps)
+  print "{}: {:,} B".format(name, total)
+  if not detailed:
+    return
+  max_size_str_len = 0
+  for item, size in histogram:
+    size_str = "{:,}".format(size)
+    padding = max(0, max_size_str_len - len(size_str))
+    max_size_str_len = max(max_size_str_len, len(size_str))
+    print "  * {}{} B: {}".format(" " * padding, size_str, item)
+
+
+def extract_total(maps):
+  return extract_mappings(maps,
+                          lambda m: True,
+                          lambda m: "Total")
+
+
+def extract_code_size(maps):
+  return extract_mappings(maps,
+                          lambda m: "ex" in m["VmFlags"],
+                          lambda m: m["path"])
+
+
+def extract_heap_size(maps):
+  return extract_mappings(maps,
+                          lambda m: m["path"] == "[heap]",
+                          lambda m: m["path"])
+
+
+def extract_stack_size(maps):
+  return extract_mappings(maps,
+                          lambda m: m["path"] == "[stack]",
+                          lambda m: m["path"])
+
+
+def extract_mapped_files(maps):
+  return extract_mappings(maps,
+                          lambda m: "/" in m["path"] and "ex" not in m["VmFlags"],
+                          lambda m: m["path"])
+
+
+def extract_other(maps):
+  return extract_mappings(maps,
+                          lambda m: "/" not in m["path"] and m["path"] != "[stack]" and m["path"] != "[heap]" and "ex" not in m["VmFlags"],
+                          lambda m: m["path"])
+
+
+def show_mem_info(pid, detailed):
+  maps = get_mappings(pid)
+  print_histogram("Total", maps, extract_total, detailed)
+  print_histogram("* Heap", maps, extract_heap_size, detailed)
+  print_histogram("* Stack", maps, extract_stack_size, detailed)
+  print_histogram("* Memory mapped files", maps, extract_mapped_files, detailed)
+  print_histogram("* Executable code", maps, extract_code_size, detailed)
+  print_histogram("* Other", maps, extract_other, detailed)
+
+
+def main():
+  parser = argparse.ArgumentParser(description="Prints the memory allocation information of a process.")
+  parser.add_argument("--detailed", action="store_true", help="Show a breakdown for each category.")
+  parser.add_argument("pid", help="PID of the process whose memory is to be analyzed.", type=int)
+  parser.set_defaults(detailed=False)
+  args = parser.parse_args()
+  show_mem_info(args.pid, args.detailed)
+
+
+if __name__ == "__main__":
+  main()