[issue44206] Add a version number to dict keys.

Pablo Galindo Salgado added the comment: Closing for now unless we see the error again -- resolution: -> fixed status: open -> closed ___ Python tracker ___

[issue44206] Add a version number to dict keys.

Pablo Galindo Salgado added the comment: New changeset e06ae75e16dbf46b6626b6a41b62391ea1fdb319 by Mark Shannon in branch 'main': bpo-44206: Make sure that dict-keys's version is set to zero when value is popped (GH-27542)

[issue44206] Add a version number to dict keys.

Pablo Galindo Salgado added the comment: Opened https://bugs.python.org/issue44808 -- stage: patch review -> resolved ___ Python tracker ___

[issue44206] Add a version number to dict keys.

Change by Mark Shannon : -- pull_requests: +26051 stage: resolved -> patch review pull_request: https://github.com/python/cpython/pull/27542 ___ Python tracker ___

[issue44206] Add a version number to dict keys.

Pablo Galindo Salgado added the comment: > Known issue or should I file a new issue? This issue is also present in 3.10. Can you open a different issue, please? -- ___ Python tracker

[issue44206] Add a version number to dict keys.

Mark Shannon added the comment: Pablo, There is another failure on that buildbot: test_inspect fails with ^^ File "/home/mark/repos/cpython/Lib/inspect.py", line 1154, in walktree classes.sort(key=attrgetter('__module__', '__name__'))

[issue44206] Add a version number to dict keys.

Pablo Galindo Salgado added the comment: Reopening this and marking as a release blocker. Seems that a buildbot has found some cases where an assert fails: https://buildbot.python.org/all/#/builders/562/builds/110/steps/5/logs/stdio ..python: Objects/dictobject.c:350: dictkeys_set_index:

[issue44206] Add a version number to dict keys.

Change by Mark Shannon : -- resolution: -> fixed stage: patch review -> resolved status: open -> closed ___ Python tracker ___ ___

[issue44206] Add a version number to dict keys.

Inada Naoki added the comment: Can we close this issue? -- ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue44206] Add a version number to dict keys.

Pablo Galindo Salgado added the comment: New changeset 1a672a5908736e44a8a25a99b3a116b085f12aa8 by Pablo Galindo in branch 'main': bpo-44206: Fix compiler warnings in dictobject.c (GH-26440) https://github.com/python/cpython/commit/1a672a5908736e44a8a25a99b3a116b085f12aa8 --

[issue44206] Add a version number to dict keys.

Change by Pablo Galindo Salgado : -- nosy: +pablogsal nosy_count: 5.0 -> 6.0 pull_requests: +25032 pull_request: https://github.com/python/cpython/pull/26440 ___ Python tracker

[issue44206] Add a version number to dict keys.

Change by Mark Shannon : -- pull_requests: +25027 pull_request: https://github.com/python/cpython/pull/26432 ___ Python tracker ___

[issue44206] Add a version number to dict keys.

Mark Shannon added the comment: New changeset f8a95df84bcedebc0aa7132b3d1a4e8f000914bc by Mark Shannon in branch 'main': bpo-44206: Add a version number to dictionary keys (GH-26333) https://github.com/python/cpython/commit/f8a95df84bcedebc0aa7132b3d1a4e8f000914bc --

[issue44206] Add a version number to dict keys.

Mark Shannon added the comment: Which optimizations? LOAD_GLOBAL: Using a keys version instead of a whole dict version means that LOAD_GLOBAL won't leak references. It also means that we can (in the future) remove the PEP 509 version and save 8 bytes per dict. LOAD_ATTR:

[issue44206] Add a version number to dict keys.

Inada Naoki added the comment: For class dict, there is a method cache. For instance dict, there is a LOAD_ATTR optimization. https://github.com/python/cpython/blob/b11a951f16f0603d98de24fee5c023df83ea552c/Python/ceval.c#L3458 So I want to see the performance gain of the optimization using

[issue44206] Add a version number to dict keys.

STINNER Victor added the comment: Can't you please explain which kind of optimizations do you want to implement using such dict key version? -- ___ Python tracker ___

[issue44206] Add a version number to dict keys.

Change by Erlend E. Aasland : -- nosy: +erlendaasland ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue44206] Add a version number to dict keys.

Mark Shannon added the comment: http://theses.gla.ac.uk/2975/1/2011shannonphd.pdf page 128. It means we don't need to cache a pointer to the keys, just the version number. The version number is half the size (for 64 bit machines) and using it means that we don't leak keys. --

[issue44206] Add a version number to dict keys.

STINNER Victor added the comment: I don't understand how such "key version" would be useful. Can you please elaborate? -- ___ Python tracker ___

[issue44206] Add a version number to dict keys.

Change by Mark Shannon : -- keywords: +patch pull_requests: +24925 stage: needs patch -> patch review pull_request: https://github.com/python/cpython/pull/26333 ___ Python tracker

[issue44206] Add a version number to dict keys.

Mark Shannon added the comment: The version is on the dict keys. It changes if the dict keys object changes in a meaningful way. So, no it doesn't change if a value is changed. Nor would it change if the keys were shared and a new key-value pair is added to a dict, but that key was already

[issue44206] Add a version number to dict keys.

STINNER Victor added the comment: > Add a version number to dict keys. Is the version on the key or on the value? Does the version change if a value is changed like d[1]="a"; d[1]="b"? -- ___ Python tracker

[issue44206] Add a version number to dict keys.

Change by Brandt Bucher : -- nosy: +brandtbucher ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue44206] Add a version number to dict keys.

Mark Shannon added the comment: The memory saving comes from converting: Py_ssize_t dk_size; dict_lookup_func dk_lookup; to: uint8_t dk_log2_size; uint8_t dk_loopup_kind; /* Only 3 possible values */ uint32_t dk_version; which saves 8 bytes on a 64 bit machine (no saving

[issue44206] Add a version number to dict keys.

New submission from Mark Shannon : Add a version number to dict keys. PEP 509 added a version number to dicts. Unfortunately this is no use for optimizing attribute loads and store on instances. We need to know whether the keys are as expected, not the dict as that is likely to be different