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Re: Poor performance of git describe in big repos

From
Ramkumar Ramachandra <artagnon@gmail.com>
Date
May 30, 2013, 14:32 UTC
Message-ID
<CALkWK0=bgM+fYcVEwjHHF8k2Q8wMmjdbM5bxXdPH6s9StDH_Ng@mail.gmail.com>
In-Reply-To
<CAJ-05NNAeLUfyk8+NU8PmjKqfTcZ1NT_NPAk3M1QROtzsQKJ8g@mail.gmail.com>
Alex Bennée wrote:
Show 8 quoted lines
> And through my "special" repo:
>
>  41.58%   git  libcrypto.so.1.0.0  [.] sha1_block_data_order_ssse3
>  33.62%   git  libz.so.1.2.3.4     [.] inflate_fast
>  10.39%   git  libz.so.1.2.3.4     [.] adler32
>   2.03%   git  [kernel.kallsyms]   [k] clear_page_c
>
>  I'm not sure why libcrypto features so highly in the results

While Duy churns on the delta chain, let me try to make a (rather crude) observation:

What does it mean for libcrypto to be so high in your perf report? sha1_block_data_order is ultimately by object.c:parse_object. While it indicates that deltas are taking a long time to apply (or are somehow not optimally organized for IO), I think it indicates either:

1. Your history is very deep and there are an unusually high number of
deltas for each blob.  What are the total number of commits?
2. You have have huge (binary) files checked into your repository.  Do
you?  If so, why isn't the code in streaming.c kicking in?
Previous: Alex BennéeNext: Alex Bennée
Message 4 of 33 in “Poor performance of git describe in big repos”
  1. Alex BennéeMay 30, 2013
  2. Ramkumar RamachandraMay 30, 2013
  3. Alex BennéeMay 30, 2013
  4. Ramkumar RamachandraMay 30, 2013
  5. Alex BennéeMay 30, 2013
  6. Ramkumar RamachandraMay 30, 2013
  7. Thomas RastMay 30, 2013
  8. Alex BennéeMay 30, 2013
  9. Thomas RastMay 30, 2013
  10. Thomas RastMay 30, 2013
  11. Antoine PelisseMay 30, 2013
  12. John KeepingMay 30, 2013
  13. Alex BennéeMay 31, 2013
  14. Thomas RastMay 31, 2013
  15. Alex BennéeMay 31, 2013
  16. Thomas RastMay 31, 2013
  17. Alex BennéeMay 31, 2013
  18. Alex BennéeJun 3, 2013
  19. Junio C HamanoJun 3, 2013
  20. Junio C HamanoJun 3, 2013
  21. Thomas RastMay 31, 2013
  22. Jeff KingMay 31, 2013
  23. Alex BennéeJun 3, 2013
  24. Jeff KingJun 3, 2013
  25. John KeepingMay 31, 2013
  26. Alex BennéeMay 31, 2013
  27. John KeepingMay 31, 2013
  28. John KeepingMay 30, 2013
  29. Alex BennéeMay 30, 2013
  30. Duy NguyenMay 30, 2013
  31. Alex BennéeMay 30, 2013
  32. Duy NguyenMay 30, 2013
  33. Alex BennéeMay 30, 2013

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