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Re: Poor performance of git describe in big repos

From
Thomas Rast <trast@inf.ethz.ch>
Date
May 30, 2013, 16:44 UTC
Message-ID
<87bo7sbeoc.fsf@linux-k42r.v.cablecom.net>
In-Reply-To
<87ip20bfq4.fsf@linux-k42r.v.cablecom.net>
Thomas Rast <trast@inf.ethz.ch> writes:
> I had a brief look around sha1_file.c, in particular sha1_object_info,
> and it turns out we lack the "deflate only early part" logic as I
> suspected.  So that'll have to be fixed first.  After that I *think* it
> should automatically carry over into the tag readers.

Strike that, I'm wrong. sha1_object_info is fast even for these big loose objects.

The culprit, according to some callgrind investigation, is lookup_commit_reference_gently() [for the unannotated case] or deref_tag() [annotated case] calling parse_object().

-- 
Thomas Rast
trast@{inf,student}.ethz.ch
Previous: Thomas RastNext: Antoine Pelisse
Message 10 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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