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Re: [PATCH] interpret_nth_last_branch(): avoid traversing the reflogs twice

From
Johannes Schindelin <johannes.schindelin@gmx.de>
Date
Jan 18, 2009, 01:12 UTC
Message-ID
<alpine.DEB.1.00.0901180201070.3586@pacific.mpi-cbg.de>
In-Reply-To
<7vmydp5tqj.fsf@gitster.siamese.dyndns.org>
Hi,
On Sat, 17 Jan 2009, Junio C Hamano wrote:
Show 7 quoted lines
> Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
> 
> > That is correct.  But this is such a highly uncritical code path that 
> > I'd like to keep this simple rather than fast.
> 
> I actually not worried about "fast" at all; it was more about unbounded 
> memory consumption.

Let's just assume that I make a branch switch per minute, continuously, for 90 days (until the reflogs are expired), and let's say that all my branchnames have 20 characters. Conservatively, the memory requirement would be 100 * 2000 * 30 = 3 megabyte.

Note: these are the memory requirements after some really unrealistically 
high activity, and the memory is free()d during parameter parsing.

A much more realistical expectation would be to switch branches maybe 20 times a day, which would amount to something like 36 kilobyte. And again, they are free()d before the action really starts.

Ciao, Dscho

Previous: Junio C HamanoNext: Junio C Hamano
Message 32 of 56 in “N-th last checked out branch”
  1. 0/6 N-th last checked out branchThomas Rast, Jan 17, 2009
  2. 1/6 reflog: refactor parsing and checkingThomas Rast, Jan 17, 2009
  3. 2/6 reflog: refactor log open+mmapThomas Rast, Jan 17, 2009
  4. 3/6 reflog: make for_each_reflog_ent use mmapThomas Rast, Jan 17, 2009
  5. 4/6 reflog: add backwards iteratorThomas Rast, Jan 17, 2009
  6. 5/6 sha1_name: implement @{-N} syntax for N-th last checked outThomas Rast, Jan 17, 2009
  7. 6/6 checkout: implement '@{-N}' and '-' special abbreviationsThomas Rast, Jan 17, 2009
  8. Johannes SchindelinJan 17, 2009
  9. Johannes SchindelinJan 17, 2009
  10. Johannes SchindelinJan 17, 2009
  11. Thomas RastJan 17, 2009
  12. 1/2 sha1_name: implement @{-N} syntax for N-th last checked outThomas Rast, Jan 17, 2009
  13. 2/2 checkout: implement '@{-N}' and '-' special abbreviationsThomas Rast, Jan 17, 2009
  14. interpret_nth_last_branch(): avoid traversing the reflogs twiceJohannes Schindelin, Jan 17, 2009
  15. 0/5 N-th last checked out branchThomas Rast, Jan 17, 2009
  16. 1/5 checkout: implement "@{-N}" shortcut name for N-th last branchThomas Rast, Jan 17, 2009
  17. 2/5 sha1_name: tweak @{-N} lookupThomas Rast, Jan 17, 2009
  18. 3/5 sha1_name: support @{-N} syntax in get_sha1()Thomas Rast, Jan 17, 2009
  19. 4/5 checkout: implement "-" abbreviation, add docs and testsThomas Rast, Jan 17, 2009
  20. 5/5 interpret_nth_last_branch(): avoid traversing the reflogs twiceThomas Rast, Jan 17, 2009
  21. 6/5 Fix parsing of @{-1}@{1}Johannes Schindelin, Jan 17, 2009
  22. Junio C HamanoJan 17, 2009
  23. Johannes SchindelinJan 17, 2009
  24. Junio C HamanoJan 17, 2009
  25. Johannes SchindelinJan 17, 2009
  26. Junio C HamanoJan 17, 2009
  27. Junio C HamanoJan 18, 2009
  28. Johannes SchindelinJan 17, 2009
  29. Junio C HamanoJan 17, 2009
  30. Johannes SchindelinJan 17, 2009
  31. Junio C HamanoJan 18, 2009
  32. Johannes SchindelinJan 18, 2009
  33. Junio C HamanoJan 18, 2009
  34. Johannes SchindelinJan 18, 2009
  35. Junio C HamanoJan 19, 2009
  36. Junio C HamanoJan 19, 2009
  37. Johannes SchindelinJan 19, 2009
  38. Thomas RastJan 20, 2009
  39. Johannes SchindelinJan 20, 2009
  40. Thomas RastJan 20, 2009
  41. interpret_nth_last_branch(): plug small memleakJunio C Hamano, Jan 20, 2009
  42. Johannes SchindelinJan 20, 2009
  43. Introduce for_each_recent_reflog_ent().Junio C Hamano, Jan 20, 2009
  44. Johannes SchindelinJan 20, 2009
  45. Junio C HamanoJan 20, 2009
  46. Fix invalid memory accessJohannes Schindelin, Jan 21, 2009
  47. Junio C HamanoJan 21, 2009
  48. Thomas RastJan 21, 2009
  49. Junio C HamanoJan 21, 2009
  50. Johannes SchindelinJan 21, 2009
  51. Thomas RastJan 24, 2009
  52. t1505: remove debugging cruftThomas Rast, Jan 24, 2009
  53. Junio C HamanoJan 25, 2009
  54. Johannes SchindelinJan 21, 2009
  55. @{-<n>}: avoid crash with corrupt reflogJohannes Schindelin, Jan 19, 2009
  56. Johannes SchindelinJan 19, 2009

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