[issue29202] Improve dict iteration

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

[issue29202] Improve dict iteration

Inada Naoki added the comment: New changeset f66e336f455b5a6bb0ca857d61c43be410d0df13 by Inada Naoki (Cheryl Sabella) in branch 'master': bpo-29202: improve dict iteration (GH-11900) https://github.com/python/cpython/commit/f66e336f455b5a6bb0ca857d61c43be410d0df13 --

[issue29202] Improve dict iteration

Change by Cheryl Sabella : -- pull_requests: +11927 ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue29202] Improve dict iteration

Raymond Hettinger added the comment: > I can convert this to a pull request if there is still interest in the change. Yes, please do. -- ___ Python tracker ___

[issue29202] Improve dict iteration

Cheryl Sabella added the comment: I can convert this to a pull request if there is still interest in the change. -- nosy: +cheryl.sabella versions: +Python 3.8 ___ Python tracker

[issue29202] Improve dict iteration

Raymond Hettinger added the comment: This doesn't meet our criteria for backports. -- assignee: rhettinger -> serhiy.storchaka versions: -Python 3.6 ___ Python tracker

[issue29202] Improve dict iteration

Serhiy Storchaka added the comment: Do you mind to create a pull request Raymond? -- ___ Python tracker ___

[issue29202] Improve dict iteration

Serhiy Storchaka added the comment: In general the idea LGTM. It it is slightly dangerous if dict structure is broken. j is incremented only when value != NULL, and if ma_used is not correct, this can cause reading out of the end of an array. Of course this should never happen. But if there

[issue29202] Improve dict iteration

INADA Naoki added the comment: While this isn't bugfix, I'm +1 to commit this to 3.6 branch to reduce future maintenance cost. -- ___ Python tracker ___

[issue29202] Improve dict iteration

Changes by Serhiy Storchaka : Added file: http://bugs.python.org/file46214/dict_shorter_iteration.diff ___ Python tracker ___

[issue29202] Improve dict iteration

INADA Naoki added the comment: patch LGTM. > Since the table is usually dense packed to the left, this will give fewer > loops and fewer memory accesses. Since dk_nentries is "right end of active entries", this patch doesn't affect for "dence packed to the left" dict. But it can affect when

[issue29202] Improve dict iteration

INADA Naoki added the comment: > I'm wondering why new dict implementation don't keep the array of items > compact? Original Raymond's implementation did not preserve the order after > deletions, but saved items in an array without gaps. This could simplify and > speed up an iteration (no

[issue29202] Improve dict iteration

Serhiy Storchaka added the comment: I'm wondering why new dict implementation don't keep the array of items compact? Original Raymond's implementation did not preserve the order after deletions, but saved items in an array without gaps. This could simplify and speed up an iteration (no need

[issue29202] Improve dict iteration

New submission from Raymond Hettinger: I haven't had much of a chance to comb through all the code it detail, but there are least a few places that loop over the whole entry table (size is dk_nentries) when fewer iterations would suffice (stop once mp->ma_used entries have been seen). Since

[issue29202] Improve dict iteration

Changes by Raymond Hettinger : -- priority: normal -> low ___ Python tracker ___