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On Tue, 10 Jun 2008 19:40:22 +0530 |
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"Arun Raghavan" <arunisgod@×××××.com> wrote: |
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> On Tue, Jun 10, 2008 at 7:32 PM, Ciaran McCreesh |
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> <ciaran.mccreesh@××××××××××.com> wrote: |
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> [...] |
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> >> I don't think that filename-vs-first-line is going to make a big |
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> >> difference in practical performance. |
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> > |
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> > It's about a factor of five difference in cold-cache resolution |
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> > performance for Paludis. |
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> |
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> Could you please share more details on the experiment that showed this |
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> kind of performance degradation and the numbers, if possible? |
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|
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Shove an open and a getline in when doing what would otherwise be a |
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successful cache read. It adds a couple of thousand new open()s on |
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files that would otherwise be left alone, and changes the nice linear |
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"slurp up things in this directory in order until we don't need |
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anything else" pattern into "bounce backwards and forwards between lots |
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of files in two different directories". |
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|
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On a cold cache, which is the most common use case, this is very very |
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nasty. |
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|
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-- |
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Ciaran McCreesh |
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