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Created on2015-12-25 12:48 byserhiy.storchaka, last changed2022-04-11 14:58 byadmin. This issue is nowclosed.
| Files | ||||
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| File name | Uploaded | Description | Edit | |
| odict___dict__.patch | serhiy.storchaka,2015-12-25 12:48 | review | ||
| Messages (4) | |||
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| msg256988 -(view) | Author: Serhiy Storchaka (serhiy.storchaka)* | Date: 2015-12-25 12:48 | |
For now OrderedDict always creates an empty dict for __dict__.>>> from collections import OrderedDict>>> import gc>>> gc.get_referents(OrderedDict())[{}]>>> class OD(OrderedDict): pass... >>> gc.get_referents(OD())[<class '__main__.OD'>, {}]But dict subclasses (as well as most other classes) create an empty dict for __dict__ only if needed.>>> class D(dict): pass... >>> d = D()>>> gc.get_referents(d)[<class '__main__.D'>]>>> d.__dict__{}>>> gc.get_referents(d)[{}, <class '__main__.D'>]This allows to save CPU time for dictionary creation and a memory (144 bytes on 32-bit, twice as much on 64-bit).Proposed patch makes __dict__ in OrderedDict to be created only if needed. | |||
| msg257044 -(view) | Author: Camilla Montonen (Winterflower) | Date: 2015-12-26 20:01 | |
Hi Serhiy, I tried to see whether the patch's unit test in test_ordered_dict.py would fail when the changes to odictobject.c were not applied and it did not. The code change to test_ordered_dict.py does not appear to test the fact that a dict is not automatically created when an ordered dict is instantiated (?). | |||
| msg258593 -(view) | Author: Serhiy Storchaka (serhiy.storchaka)* | Date: 2016-01-19 13:56 | |
The patch have no visible effect, except lesser memory consumption. The latter is hard to measure in tests. Additional tests just ensure that the patch doesn't break existing behavior. | |||
| msg259849 -(view) | Author: Roundup Robot (python-dev) | Date: 2016-02-08 14:39 | |
New changesetcaab6b356a9e by Serhiy Storchaka in branch 'default':Issue#25949: __dict__ for an OrderedDict instance is now created only whenhttps://hg.python.org/cpython/rev/caab6b356a9e | |||
| History | |||
|---|---|---|---|
| Date | User | Action | Args |
| 2022-04-11 14:58:25 | admin | set | github: 70137 |
| 2017-04-25 01:18:03 | jcea | set | nosy: +jcea |
| 2016-02-08 14:40:06 | serhiy.storchaka | set | status: open -> closed resolution: fixed stage: patch review -> resolved |
| 2016-02-08 14:39:36 | python-dev | set | nosy: +python-dev messages: +msg259849 |
| 2016-01-19 13:56:45 | serhiy.storchaka | set | assignee:serhiy.storchaka messages: +msg258593 |
| 2015-12-26 20:01:16 | Winterflower | set | nosy: +Winterflower messages: +msg257044 |
| 2015-12-25 12:48:08 | serhiy.storchaka | create | |