mono-heapviz

#!/usr/bin/env python

# Generate a heap visualization for SGen from the heap dump written by
# mono if the MONO_GC_DEBUG is set to something like
# "heap-dump=/path/to/file".  This script accepts the file as stdin
# and generates HTML and PNG files.

from __future__ import print_function
import sys, os
import Image, ImageDraw
from xml.sax import ContentHandler, make_parser
from xml.sax.handler import feature_namespaces
from optparse import OptionParser

chunk_size = 1024                       # number of bytes in a chunk
chunk_pixel_size = 2                    # a chunk is a square with this side length
large_sections = False

def mark_chunk (img_draw, i, color, section_width):
    row = i / section_width
    col = i % section_width
    pixel_col = col * chunk_pixel_size
    pixel_row = row * chunk_pixel_size
    img_draw.rectangle ([(pixel_col, pixel_row), (pixel_col + chunk_pixel_size - 1, pixel_row + chunk_pixel_size - 1)], fill = color)

class Range:
    pass

class OccupiedRange (Range):
    def __init__ (self, offset, size):
        self.offset = offset
        self.size = size

    def mark (self, img_draw, color, section_width):
        start = self.offset / chunk_size
        end = (self.offset + self.size - 1) / chunk_size
        for i in range (start, end + 1):
            mark_chunk (img_draw, i, color, section_width)

class ObjectRange (OccupiedRange):
    def __init__ (self, klass, offset, size):
        OccupiedRange.__init__ (self, offset, size)
        self.klass = klass;

class SectionHandler:
    def __init__ (self, width):
        self.width = width
        self.ranges = []
        self.size = 0
        self.used = 0

    def add_object (self, klass, offset, size):
        self.ranges.append (ObjectRange (klass, offset, size))
        self.used += size

    def add_occupied (self, offset, size):
        self.ranges.append (OccupiedRange (offset, size))
        self.used += size

    def draw (self):
        height = (((self.size / chunk_size) + (self.width - 1)) / self.width) * chunk_pixel_size

        color_background = (255, 255, 255)
        color_free = (0, 0, 0)
        color_occupied = (0, 255, 0)

        img = Image.new ('RGB', (self.width * chunk_pixel_size, height), color_free)
        img_draw = ImageDraw.Draw (img)
        #FIXME: remove filling after end of heap

        for r in self.ranges:
            r.mark (img_draw, color_occupied, self.width)

        return img

    def emit (self, collection_file, collection_kind, collection_num, section_num):
        print ('<h2>%s</h2>' % self.header (), file = collection_file)
        print ('<p>Size %d kB - ' % (self.size / 1024), file = collection_file)
        print ('used %d kB</p>' % (self.used / 1024), file = collection_file)

        filename = '%s_%d_%d.png' % (collection_kind, collection_num, section_num)
        print ('<p><img src="%s"></img></p>' % filename, file = collection_file)
        img = self.draw ()
        img.save (filename)

class SmallSectionHandler (SectionHandler):
    def __init__ (self):
        SectionHandler.__init__ (self, -1)
        self.offset = 0

    def start_section (self, kind, size):
        assert kind == 'old'
        if self.width <= 0:
            self.width = (size + chunk_size - 1) / chunk_size
            if self.width < 128:
                self.width = 512
                self.current_section_size = size
            else:
                self.current_section_size = self.width * chunk_size
        self.size += size

    def add_object (self, klass, offset, size):
        SectionHandler.add_object (self, klass, self.offset + offset, size)

    def add_occupied (self, offset, size):
        SectionHandler.add_occupied (self, self.offset + offset, size)

    def end_section (self):
        self.offset += self.current_section_size

    def header (self):
        return 'old sections'

class LargeSectionHandler (SectionHandler):
    def __init__ (self):
        SectionHandler.__init__ (self, 512)

    def start_section (self, kind, size):
        self.kind = kind
        self.ranges = []
        self.size = size
        self.used = 0

    def end_section (self):
        pass

    def header (self):
        return self.kind + ' section'

class DocHandler (ContentHandler):
    def start (self):
        self.collection_index = 0
        self.index_file = open ('index.html', 'w')
        print ('<html><body>', file = self.index_file)

    def end (self):
        print ('</body></html>', file = self.index_file)
        self.index_file.close ()

    def startElement (self, name, attrs):
        if name == 'collection':
            self.collection_kind = attrs.get('type', None)
            self.collection_num = int(attrs.get('num', None))
            reason = attrs.get('reason', None)
            if reason:
                reason = ' (%s)' % reason
            else:
                reason = ''
            self.section_num = 0
            filename = 'collection_%d.html' % self.collection_index
            print ('<a href="%s">%s%s collection %d</a>' % (filename, self.collection_kind, reason, self.collection_num), file = self.index_file)
            self.collection_file = open (filename, 'w')
            print ('<html><body>', file = self.collection_file)
            print ('<p><a href="collection_%d.html">Prev</a> <a href="collection_%d.html">Next</a> <a href="index.html">Index</a></p>' % (self.collection_index - 1, self.collection_index + 1), file = self.collection_file)
            print ('<h1>%s collection %d</h1>' % (self.collection_kind, self.collection_num), file = self.collection_file)
            self.usage = {}
            self.los_usage = {}
            self.pinned_usage = {}
            self.occupancies = {}
            self.in_los = False
            self.in_pinned = False
            self.heap_used = 0
            self.heap_size = 0
            self.los_size = 0
            if large_sections:
                self.section_handler = LargeSectionHandler ()
            else:
                self.section_handler = self.small_section_handler = SmallSectionHandler ()
        elif name == 'pinned':
            kind = attrs.get('type', None)
            bytes = int(attrs.get('bytes', None))
            print ('Pinned from %s: %d kB<br>' % (kind, bytes / 1024), file = self.collection_file)
        elif name == 'occupancy':
            size = int (attrs.get ('size', None))
            available = int (attrs.get ('available', None))
            used = int (attrs.get ('used', None))
            unused = available - used

            print ('Occupancy of %d byte slots: %d / %d (%d kB / %d%% wasted)<br>' % (size, used, available, unused * size / 1024, unused * 100 / available), file = self.collection_file)
        elif name == 'section':
            kind = attrs.get('type', None)
            size = int(attrs.get('size', None))

            self.heap_size += size

            if not large_sections:
                if kind == 'nursery':
                    self.section_handler = LargeSectionHandler ()
                else:
                    self.section_handler = self.small_section_handler

            self.section_handler.start_section (kind, size)
        elif name == 'object':
            klass = attrs.get('class', None)
            size = int(attrs.get('size', None))

            if self.in_los:
                usage_dict = self.los_usage
                self.los_size += size
            elif self.in_pinned:
                location = attrs.get('location', None)
                if location not in self.pinned_usage:
                    self.pinned_usage[location] = {}
                usage_dict = self.pinned_usage[location]
            else:
                usage_dict = self.usage
                offset = int(attrs.get('offset', None))

                self.section_handler.add_object (klass, offset, size)
                self.heap_used += size
            if not (klass in usage_dict):
                usage_dict [klass] = (0, 0)
            usage = usage_dict [klass]
            usage_dict [klass] = (usage [0] + 1, usage [1] + size)
        elif name == 'occupied':
            offset = int(attrs.get('offset', None))
            size = int(attrs.get('size', None))

            self.section_handler.add_occupied (offset, size)
            self.heap_used += size
        elif name == 'los':
            self.in_los = True
        elif name == 'pinned-objects':
            self.in_pinned = True

    def dump_usage (self, usage_dict, limit):
        klasses = sorted (usage_dict.keys (), lambda x, y: usage_dict [y][1] - usage_dict [x][1])
        if limit:
            klasses = klasses [0:limit]
        for klass in klasses:
            usage = usage_dict [klass]
            if usage [1] < 100000:
                print ('%s %d bytes' % (klass, usage [1]), file = self.collection_file)
            else:
                print ('%s %d kB' % (klass, usage [1] / 1024), file = self.collection_file)
            print (' (%d)<br>' % usage [0], file = self.collection_file)

    def endElement (self, name):
        if name == 'section':
            self.section_handler.end_section ()

            if large_sections or self.section_handler != self.small_section_handler:
                self.section_handler.emit (self.collection_file, self.collection_kind, self.collection_num, self.section_num)
                self.section_num += 1
        elif name == 'collection':
            if not large_sections:
                self.small_section_handler.emit (self.collection_file, self.collection_kind, self.collection_num, self.section_num)

            self.dump_usage (self.usage, 10)
            print ('<h3>LOS</h3>', file = self.collection_file)
            self.dump_usage (self.los_usage, None)
            print ('<h3>Pinned</h3>', file = self.collection_file)
            for location in sorted (self.pinned_usage.keys ()):
                print ('<h4>%s</h4>' % location, file = self.collection_file)
                self.dump_usage (self.pinned_usage[location], None)
            print ('</body></html>', file = self.collection_file)
            print (' - %d kB / %d kB (%d%%) - %d kB LOS</a><br>' % (self.heap_used / 1024, self.heap_size / 1024, int(100.0 * self.heap_used / self.heap_size), self.los_size / 1024), file = self.index_file)
            self.collection_file.close ()
            self.collection_index += 1
        elif name == 'los':
            self.in_los = False
        elif name == 'pinned-objects':
            self.in_pinned = False

def main ():
    usage = "usage: %prog [options]"
    parser = OptionParser (usage)
    parser.add_option ("-l", "--large-sections", action = "store_true", dest = "large_sections")
    parser.add_option ("-s", "--small-sections", action = "store_false", dest = "large_sections")
    (options, args) = parser.parse_args ()
    if options.large_sections:
        large_sections = True

    dh = DocHandler ()
    parser = make_parser ()
    parser.setFeature (feature_namespaces, 0)
    parser.setContentHandler (dh)
    dh.start ()
    parser.parse (sys.stdin)
    dh.end ()

if __name__ == "__main__":
    main ()