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Re: Performance problem, long run of identical hashes

From
Nicolas Pitre <nico@cam.org>
Date
Dec 10, 2007, 15:45 UTC
Message-ID
<alpine.LFD.0.99999.0712101037270.555@xanadu.home>
In-Reply-To
<9e4733910712100707i66e185bofe22805b8e0ba4d8@mail.gmail.com>
On Mon, 10 Dec 2007, Jon Smirl wrote:
> Running oprofile during my gcc repack shows this loop as the hottest
> place in the code by far.
Well, that is kind of expected.
> I added some debug printfs which show that I
> have a 100,000+ run of identical hash entries. Processing the 100,000
> entries also causes RAM consumption to explode.

That is impossible. If you look at the code where those hash entries are created in create_delta_index(), you'll notice a hard limit of HASH_LIMIT (currently 64) is imposed on the number of identical hash entries.

Nicolas
Previous: Jon SmirlNext: David Kastrup
Message 2 of 7 in “Performance problem, long run of identical hashes”
  1. Jon SmirlDec 10, 2007
  2. Nicolas PitreDec 10, 2007
  3. David KastrupDec 10, 2007
  4. Jon SmirlDec 10, 2007
  5. Nicolas PitreDec 10, 2007
  6. David KastrupDec 10, 2007
  7. Nicolas PitreDec 10, 2007

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