Ticket #17: instance-caching-2.patch

File instance-caching-2.patch, 20.9 KB (added by (removed), 8 years ago)

instance-caching-v2

  • django/core/serializers/python.py

    # Bazaar revision bundle v0.9
    #
    # message:
    #   update select_related tests with proper counts; basically heavy reduction of # of queries required via instance caching tricks in foreign key backref instances
    # committer: Brian Harring <ferringb@gmail.com>
    # date: Sun 2007-05-27 10:21:20.177999973 -0700
    
    === modified file django/core/serializers/python.py // last-changed:ferringb@gm
    ... ail.com-20070525002257-juow7h2cfizoox5u
     
    8989            else:
    9090                data[field.name] = field.to_python(field_value)
    9191               
     92        data["disable_inst_caching"] = True
    9293        yield base.DeserializedObject(Model(**data), m2m_data)
    9394
    9495def _get_model(model_identifier):
  • django/core/serializers/xml_serializer.py

    === modified file django/core/serializers/xml_serializer.py // last-changed:fer
    ... ringb@gmail.com-20070525001853-wnodu5zd8vdcda59
     
    170170                    value = field.to_python(getInnerText(field_node).strip().encode(self.encoding))
    171171                data[field.name] = value
    172172       
     173        data["disable_inst_caching"] = True
    173174        # Return a DeserializedObject so that the m2m data has a place to live.
    174175        return base.DeserializedObject(Model(**data), m2m_data)
    175176       
     
    226227            inner_text.extend(getInnerText(child))
    227228        else:
    228229           pass
    229     return "".join(inner_text)
    230  No newline at end of file
     230    return "".join(inner_text)
  • django/db/models/base.py

    === modified file django/db/models/base.py // last-changed:ferringb@gmail.com-2
    ... 0070525001853-wnodu5zd8vdcda59
     
    1414from django.utils.functional import curry
    1515from django.conf import settings
    1616from itertools import izip
     17from weakref import WeakValueDictionary
    1718import types
    1819import sys
    1920import os
     
    7677        # registered version.
    7778        return get_model(new_class._meta.app_label, name, False)
    7879
     80    def __call__(cls, *args, **kwargs):
     81        if not kwargs.pop("disable_inst_caching", False) and cls._meta.has_auto_field:
     82            key = cls._get_cache_key(args, kwargs)
     83            if key is not None:
     84                obj = cls.__instance_cache__.get(key)
     85                if obj is None:
     86                    obj = super(ModelBase, cls).__call__(*args, **kwargs)
     87                    cls.__instance_cache__[key] = obj
     88            else:
     89                obj = super(ModelBase, cls).__call__(*args, **kwargs)
     90        else:
     91            obj = super(ModelBase, cls).__call__(*args, **kwargs)
     92        return obj
     93
     94
    7995class Model(object):
    8096    __metaclass__ = ModelBase
    8197
     
    94110    def __ne__(self, other):
    95111        return not self.__eq__(other)
    96112
     113    def _get_cache_key(cls, args, kwargs):
     114        # this should be calculated *once*, but isn't atm
     115        pk_position = cls._meta.fields.index(cls._meta.pk)
     116        if len(args) > pk_position:
     117            return args[pk_position]
     118        pk = cls._meta.pk
     119        if pk.name in kwargs:
     120            return kwargs[pk.name]
     121        elif pk.attname in kwargs:
     122            return kwargs[pk.attname]
     123        return None
     124    _get_cache_key = classmethod(_get_cache_key)
     125
     126    def get_cached_instance(cls, id):
     127        return cls.__instance_cache__.get(id)
     128    get_cached_instance = classmethod(get_cached_instance)
     129
    97130    def __init__(self, *args, **kwargs):
    98131        dispatcher.send(signal=signals.pre_init, sender=self.__class__, args=args, kwargs=kwargs)
    99132       
     
    194227        if hasattr(cls, 'get_absolute_url'):
    195228            cls.get_absolute_url = curry(get_absolute_url, opts, cls.get_absolute_url)
    196229
     230        cls.__instance_cache__ = WeakValueDictionary()
     231
    197232        dispatcher.send(signal=signals.class_prepared, sender=cls)
    198233
    199234    _prepare = classmethod(_prepare)
     
    251286                setattr(self, self._meta.pk.attname, backend.get_last_insert_id(cursor, self._meta.db_table, self._meta.pk.column))
    252287        transaction.commit_unless_managed()
    253288
     289        # if we're a new instance that hasn't been written in; save ourself.
     290        if self._meta.has_auto_field:
     291            self.__instance_cache__[getattr(self, self._meta.pk.attname)] = self
     292
    254293        # Run any post-save hooks.
    255294        dispatcher.send(signal=signals.post_save, sender=self.__class__, instance=self)
    256295
  • django/db/models/fields/related.py

    === modified file django/db/models/fields/related.py // last-changed:ferringb@g
    ... mail.com-20070524150447-bxe88y4c8ixjsqqa
     
    163163                if self.field.null:
    164164                    return None
    165165                raise self.field.rel.to.DoesNotExist
    166             other_field = self.field.rel.get_related_field()
    167             if other_field.rel:
    168                 params = {'%s__pk' % self.field.rel.field_name: val}
    169             else:
    170                 params = {'%s__exact' % self.field.rel.field_name: val}
    171             rel_obj = self.field.rel.to._default_manager.get(**params)
     166            rel_obj = self.field.rel.to.get_cached_instance(val)
     167            if rel_obj is None:
     168                other_field = self.field.rel.get_related_field()
     169                if other_field.rel:
     170                    params = {'%s__pk' % self.field.rel.field_name: val}
     171                else:
     172                    params = {'%s__exact' % self.field.rel.field_name: val}
     173                rel_obj = self.field.rel.to._default_manager.get(**params)
    172174            setattr(instance, cache_name, rel_obj)
    173175            return rel_obj
    174176
  • tests/modeltests/model_forms/models.py

    === modified file tests/modeltests/model_forms/models.py // last-changed:ferrin
    ... gb@gmail.com-20070525002908-88uk1p54t5xwec3w
     
    2442441
    245245>>> test_art = Article.objects.get(id=1)
    246246>>> test_art.headline
    247 'Test headline'
     247u'Test headline'
    248248
    249249You can create a form over a subset of the available fields
    250250by specifying a 'fields' argument to form_for_instance.
     
    2602601
    261261>>> new_art = Article.objects.get(id=1)
    262262>>> new_art.headline
    263 'New headline'
     263u'New headline'
    264264
    265265Add some categories and test the many-to-many form output.
    266266>>> new_art.categories.all()
  • tests/modeltests/select_related/models.py

    === modified file tests/modeltests/select_related/models.py
     
    1071071
    108108
    109109# select_related() also of course applies to entire lists, not just items.
    110 # Without select_related()
     110# Without select_related() (note instance caching still reduces this from 9 to 5)
    111111>>> db.reset_queries()
    112112>>> world = Species.objects.all()
    113113>>> [o.genus.family for o in world]
    114114[<Family: Drosophilidae>, <Family: Hominidae>, <Family: Fabaceae>, <Family: Amanitacae>]
    115115>>> len(db.connection.queries)
    116 9
     1165
    117117
    118118# With select_related():
    119119>>> db.reset_queries()
     
    129129>>> pea.genus.family.order.klass.phylum.kingdom.domain
    130130<Domain: Eukaryota>
    131131
    132 # Notice: one few query than above because of depth=1
     132# notice: instance caching saves the day; would be 7 without.
    133133>>> len(db.connection.queries)
    134 7
     1341
    135135
    136136>>> db.reset_queries()
    137137>>> pea = Species.objects.select_related(depth=5).get(name="sativum")
    138138>>> pea.genus.family.order.klass.phylum.kingdom.domain
    139139<Domain: Eukaryota>
    140140>>> len(db.connection.queries)
    141 3
     1411
    142142
    143143>>> db.reset_queries()
    144144>>> world = Species.objects.all().select_related(depth=2)
    145145>>> [o.genus.family.order for o in world]
    146146[<Order: Diptera>, <Order: Primates>, <Order: Fabales>, <Order: Agaricales>]
    147147>>> len(db.connection.queries)
    148 5
     1481
    149149
    150150# Reset DEBUG to where we found it.
    151151>>> settings.DEBUG = False
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