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Re: Why SHA are 40 bytes? (aka looking for flames)

From
MCMarco Costalba <mcostalba@gmail.com>
Date
Apr 21, 2007, 17:06 UTC
Message-ID
<e5bfff550704211006t59cb49h179685d694a1d75a@mail.gmail.com>
In-Reply-To
<9e4733910704210837y3ac3654ekb60654ef6fc397fc@mail.gmail.com>
On 4/21/07, Jon Smirl <jonsmirl@gmail.com> wrote:
Show 8 quoted lines
> On 4/21/07, Marco Costalba <mcostalba@gmail.com> wrote:
> > Well, why to store always the full length SHA?
>
> When Shawn gets done with full compression the SHAs would get stored
> in the packfile once  and then be replaced with a token generated from
> the compression algorithm. Compression tokens are designed to use the
> minimal number of bits depending on frequency of occurrence.
>

Currently in Lunux tree there are about 445.424 objects (git count-objects -v), if each object has his 40 bytes name it is about 20MB to store sha *once*, probably with no real disambiguate need to be that much.

Marco
Previous: Jon SmirlNext: Jon Smirl
Message 7 of 18 in “Why SHA are 40 bytes? (aka looking for flames)”
  1. Marco CostalbaApr 21, 2007
  2. Andy ParkinsApr 21, 2007
  3. Karl HasselströmApr 21, 2007
  4. Marco CostalbaApr 21, 2007
  5. Marco CostalbaApr 21, 2007
  6. Jon SmirlApr 21, 2007
  7. Marco CostalbaApr 21, 2007
  8. Jon SmirlApr 21, 2007
  9. Marco CostalbaApr 21, 2007
  10. Jon SmirlApr 21, 2007
  11. Andreas EricssonApr 24, 2007
  12. Nicolas PitreApr 24, 2007
  13. Andreas EricssonApr 24, 2007
  14. Nicolas PitreApr 24, 2007
  15. Nicolas PitreApr 22, 2007
  16. H. Peter AnvinApr 24, 2007
  17. Shawn O. PearceApr 24, 2007
  18. Nicolas PitreApr 24, 2007

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