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Re: Make the git codebase thread-safe

From
Erik Faye-Lund <kusmabite@gmail.com>
Date
Feb 12, 2014, 18:27 UTC
Message-ID
<CABPQNSZtQd51gQY7oK8B-BbpNEhxR-onQtiXSfW9sv1t2YW_nw@mail.gmail.com>
In-Reply-To
<CAHOQ7J8QxfvtrS2KdgzUPvkDzJ1Od0CMvdWxrF_bNacVRYOa5Q@mail.gmail.com>
On Wed, Feb 12, 2014 at 7:20 PM, Stefan Zager <szager@google.com> wrote:
Show 18 quoted lines
> On Wed, Feb 12, 2014 at 3:59 AM, Erik Faye-Lund <kusmabite@gmail.com> wrote:
>> On Wed, Feb 12, 2014 at 2:54 AM, Stefan Zager <szager@chromium.org> wrote:
>>>
>>> We are particularly concerned with the performance of msysgit, and we
>>> have already chalked up a significant performance gain by turning on
>>> the threading code in pack-objects (which was already enabled for
>>> posix platforms, but not on msysgit, owing to the lack of a correct
>>> pread implementation).
>>
>> How did you manage to do this? I'm not aware of any way to implement
>> pread on Windows (without going down the insanity-path of wrapping and
>> potentially locking inside every IO operation)...
>
> I don't want to steal the thunder of my coworker, who wrote the
> implementation.  He plans to submit it upstream soon-ish.  It relies
> on using the lpOverlapped argument to ReadFile(), with some additional
> tomfoolery to make sure that the implicit position pointer for the
> file descriptor doesn't get modified.

Is the code available somewhere? I'm especially interested in the "additional tomfoolery to make sure that the implicit position pointer for the file descriptor doesn't get modified"-part, as this was what I ended up butting my head into when trying to do this myself.

Previous: Stefan ZagerNext: Stefan Zager
Message 25 of 55 in “Make the git codebase thread-safe”
  1. Stefan ZagerFeb 12, 2014
  2. Robin H. JohnsonFeb 12, 2014
  3. Duy NguyenFeb 12, 2014
  4. Karsten BleesFeb 12, 2014
  5. Mike HommeyFeb 12, 2014
  6. Karsten BleesFeb 13, 2014
  7. Stefan ZagerFeb 12, 2014
  8. Duy NguyenFeb 12, 2014
  9. Stefan ZagerFeb 12, 2014
  10. Matthieu MoyFeb 12, 2014
  11. Stefan ZagerFeb 12, 2014
  12. David KastrupFeb 12, 2014
  13. Stefan ZagerFeb 12, 2014
  14. David KastrupFeb 12, 2014
  15. Mike HommeyFeb 12, 2014
  16. David KastrupFeb 13, 2014
  17. Mike HommeyFeb 13, 2014
  18. Mike HommeyFeb 13, 2014
  19. David KastrupFeb 13, 2014
  20. Junio C HamanoFeb 12, 2014
  21. Stefan ZagerFeb 12, 2014
  22. Junio C HamanoFeb 12, 2014
  23. Erik Faye-LundFeb 12, 2014
  24. Stefan ZagerFeb 12, 2014
  25. Erik Faye-LundFeb 12, 2014
  26. Stefan ZagerFeb 12, 2014
  27. Erik Faye-LundFeb 12, 2014
  28. Karsten BleesFeb 12, 2014
  29. Stefan ZagerFeb 12, 2014
  30. Johannes SixtFeb 13, 2014
  31. David KastrupFeb 13, 2014
  32. Stefan ZagerFeb 13, 2014
  33. Zachary TurnerFeb 13, 2014
  34. Karsten BleesFeb 13, 2014
  35. Stefan ZagerFeb 13, 2014
  36. Zachary TurnerFeb 13, 2014
  37. Karsten BleesFeb 14, 2014
  38. Stefan ZagerFeb 14, 2014
  39. brian m. carlsonFeb 13, 2014
  40. Matheus TavaresApr 2, 2019
  41. Duy NguyenApr 2, 2019
  42. David KastrupApr 2, 2019
  43. Duy NguyenApr 2, 2019
  44. David KastrupApr 2, 2019
  45. Matheus Tavares BernardinoApr 2, 2019
  46. Zachary TurnerFeb 14, 2014
  47. Karsten BleesFeb 14, 2014
  48. Duy NguyenFeb 15, 2014
  49. Stefan ZagerFeb 15, 2014
  50. Duy NguyenFeb 15, 2014
  51. Zachary TurnerFeb 15, 2014
  52. Duy NguyenFeb 15, 2014
  53. Junio C HamanoFeb 18, 2014
  54. Zachary TurnerFeb 18, 2014
  55. Stefan ZagerFeb 14, 2014

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