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Re: [PATCH 1/5] diff_tree_sha1: skip diff_tree if old == new

From
Dan McGee <dpmcgee@gmail.com>
Date
Mar 31, 2011, 13:56 UTC
Message-ID
<AANLkTi=sShiwiRMF+cgiWimO80FBRKNmskwTb4JYZeSG@mail.gmail.com>
In-Reply-To
<AANLkTinwovtXfm-OvVivwyjs2RT8+D6Mj=OXkQCNH8uy@mail.gmail.com>
On Thu, Mar 31, 2011 at 7:58 AM, Nguyen Thai Ngoc Duy <pclouds@gmail.com> wrote:
Show 12 quoted lines
> On Thu, Mar 31, 2011 at 8:37 AM, Dan McGee <dpmcgee@gmail.com> wrote:
>> These next few patches are all derived from trying to make operations on this
>> repository a bit faster:
>>    http://projects.archlinux.org/svntogit/packages.git/
>>
>> ...
>>
>> time git log -- zzzzz_not_exist >/dev/null
>>                          35.558s      0.976s
>
> Do you have numbers before and after applying this series? It'd be
> interesting to see how much we gain from the series.
Whipped some up for you:

Repo Operation master after delta arch-packages ../git/git-log 2.26 2.27 -0.01 arch-packages ../git/git-log -- zzzzz_not_exist 34.69 26.75 7.93 arch-packages ../git/git-log -- aaaaa_first 6.02 5.76 0.26 linux-2.6 ../git/git-log 5.51 5.50 0.02 linux-2.6 ../git/git-log -- zzzzz_not_exist 0.95 0.92 0.03 linux-2.6 ../git/git-log -- aaaaa_first 0.89 0.86 0.03

These are all the "real" value from time with the full set of patches applied. As you can see, one either gains or isn't really affected by these; anything under 0.05s delta is noise.

Bigger gains than this don't seem too plausible unless we move away from linear parsing and traversal of tree objects.

-Dan
Previous: Nguyen Thai Ngoc DuyNext: Junio C Hamano
Message 23 of 30 in “diff_tree_sha1: skip diff_tree if old == new”
  1. 1/5 diff_tree_sha1: skip diff_tree if old == newDan McGee, Mar 31, 2011
  2. 2/5 tree-walk: drop unused parameter from match_dir_prefixDan McGee, Mar 31, 2011
  3. Dan McGeeAug 30, 2011
  4. 3/5 tree-walk: micro-optimization in tree_entry_interestingDan McGee, Mar 31, 2011
  5. Nguyen Thai Ngoc DuyApr 3, 2011
  6. Junio C HamanoApr 3, 2011
  7. Dan McGeeApr 5, 2011
  8. tree_entry_interesting: inline strncmp()Nguyễn Thái Ngọc Duy, Apr 4, 2011
  9. 4/5 tree-walk: unroll get_mode since loop boundaries are well-knownDan McGee, Mar 31, 2011
  10. Nguyen Thai Ngoc DuyApr 2, 2011
  11. Dan McGeeApr 2, 2011
  12. Nguyen Thai Ngoc DuyApr 3, 2011
  13. Erik Faye-LundApr 4, 2011
  14. Andreas EricssonApr 4, 2011
  15. Junio C HamanoApr 4, 2011
  16. Dan McGeeApr 5, 2011
  17. Antriksh PanyApr 5, 2011
  18. Dan McGeeApr 6, 2011
  19. 5/5 tree-walk: match_entry microoptimizationDan McGee, Mar 31, 2011
  20. Nguyen Thai Ngoc DuyApr 2, 2011
  21. Dan McGeeApr 2, 2011
  22. Nguyen Thai Ngoc DuyMar 31, 2011
  23. Dan McGeeMar 31, 2011
  24. Junio C HamanoApr 1, 2011
  25. Nguyen Thai Ngoc DuyMay 3, 2011
  26. Fwd: [PATCH 1/5] diff_tree_sha1: skip diff_tree if old == newDan McGee, Apr 2, 2011
  27. Dan McGeeAug 30, 2011
  28. Junio C HamanoAug 30, 2011
  29. 1/2 tree-walk: drop unused parameter from match_dir_prefixDan McGee, Sep 9, 2011
  30. 2/2 tree-walk: micro-optimization in tree_entry_interestingDan McGee, Sep 9, 2011

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