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Re: diffcore-rename performance mode

From
Jeff King <peff@peff.net>
Date
Sep 18, 2007, 09:01 UTC
Message-ID
<20070918090105.GA11854@coredump.intra.peff.net>
In-Reply-To
<7vhclswdsm.fsf@gitster.siamese.dyndns.org>
On Tue, Sep 18, 2007 at 01:58:17AM -0700, Junio C Hamano wrote:
Show 7 quoted lines
> > I thought we were holding counts of hashes, in which case there _is_ no
> > overflow.
> 
> The raw hashval (the fingerprint recorded in struct spanhash) is
> further reduced and used as an index into spahash_top.data[].
> So more than one hashval can try to sit in the same slot in
> spanhash_top.data[] array.

Right, that's sort of what I was hinting at in the original message. Can we just make the hash table big enough to use the fingerprint hashes directly? It's going to use a bit more memory, but lookups should be very fast. I'll try to experiment and get some numbers.

-Peff
Previous: Junio C HamanoNext: Junio C Hamano
Message 5 of 13 in “diffcore-rename performance mode”
  1. Jeff KingSep 18, 2007
  2. Junio C HamanoSep 18, 2007
  3. Jeff KingSep 18, 2007
  4. Junio C HamanoSep 18, 2007
  5. Jeff KingSep 18, 2007
  6. Junio C HamanoSep 18, 2007
  7. Johannes SchindelinSep 18, 2007
  8. Jeff KingSep 25, 2007
  9. Jeff KingSep 25, 2007
  10. Andreas EricssonSep 25, 2007
  11. David KastrupSep 25, 2007
  12. Jeff KingSep 25, 2007
  13. Linus TorvaldsSep 18, 2007

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