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Re: [PATCH] describe: Don’t look up commits with --exact-match

From
SZEDER Gábor <szeder@ira.uka.de>
Date
Dec 7, 2010, 09:58 UTC
Message-ID
<20101207095818.GB1867@neumann>
In-Reply-To
<alpine.DEB.2.02.1012061159500.23348@dr-wily.mit.edu>
Hi,
On Mon, Dec 06, 2010 at 12:28:59PM -0500, Anders Kaseorg wrote:
> This makes ‘git describe --exact-match HEAD’ about 15 times faster on
> a cold cache (2.3s instead of 35s) in a linux-2.6 repository with many
> packed tags.  That’s a huge win for the interactivity of the __git_ps1
> shell prompt helper.

I wanted to give it a try to see the performance improvements in the bash prompt for myself, but couldn't get to it so far. However, glancing through the logic finding out the current branch in __git_ps1, it seems that git describe is only run when git symbolic-ref HEAD failed, i.e. when on a detached head. So the performance improvement in the shell prompt is only there when on a detached head (and with lots of tags), right? If so, then I'd like to have "when on a detached head" appended to the commit message.

Best, Gábor

Previous: Jonathan NiederNext: Anders Kaseorg
Message 9 of 28 in “describe: Don’t look up commits with --exact-match”
  1. describe: Don’t look up commits with --exact-matchAnders Kaseorg, Nov 17, 2010
  2. Jonathan NiederDec 3, 2010
  3. Anders KaseorgDec 6, 2010
  4. describe: Don’t look up commits with --exact-matchAnders Kaseorg, Dec 6, 2010
  5. Jonathan NiederDec 6, 2010
  6. Thomas RastDec 6, 2010
  7. Anders KaseorgDec 6, 2010
  8. Jonathan NiederDec 6, 2010
  9. SZEDER GáborDec 7, 2010
  10. 1/2 describe: Use for_each_rawrefAnders Kaseorg, Dec 7, 2010
  11. 2/2 describe: Don’t look up commits with --exact-matchAnders Kaseorg, Dec 7, 2010
  12. Anders KaseorgDec 7, 2010
  13. Junio C HamanoDec 7, 2010
  14. Junio C HamanoDec 7, 2010
  15. Junio C HamanoDec 7, 2010
  16. Anders KaseorgDec 8, 2010
  17. 1/4 describe: Use for_each_rawrefAnders Kaseorg, Dec 8, 2010
  18. 2/4 describe: Don’t use a flex array in struct commit_nameAnders Kaseorg, Dec 8, 2010
  19. 3/4 describe: Store commit_names in a hash table by commit SHA1Anders Kaseorg, Dec 8, 2010
  20. 3/4 describe: Store commit_names in a hash table by commit SHA1Anders Kaseorg, Dec 8, 2010
  21. Junio C HamanoDec 8, 2010
  22. 4/4 describe: Delay looking up commits until searching for an inexact matchAnders Kaseorg, Dec 8, 2010
  23. Junio C HamanoDec 8, 2010
  24. Anders KaseorgDec 8, 2010
  25. 1/4 describe: Use for_each_rawrefAnders Kaseorg, Dec 9, 2010
  26. 2/4 describe: Don’t use a flex array in struct commit_nameAnders Kaseorg, Dec 9, 2010
  27. 3/4 describe: Store commit_names in a hash table by commit SHA1Anders Kaseorg, Dec 9, 2010
  28. 4/4 describe: Delay looking up commits until searching for an inexact matchAnders Kaseorg, Dec 9, 2010

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