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Re: [PATCH 0/2] optimizing pack access on "read only" fetch repos

From
Jeff King <peff@peff.net>
Date
Feb 1, 2013, 09:14 UTC
Message-ID
<20130201091431.GC30644@sigill.intra.peff.net>
In-Reply-To
<CAJo=hJuGw8x=VrjWhvZhzakuhWrCWr2FRuEsNt5gQNC=6PPuVw@mail.gmail.com>
On Thu, Jan 31, 2013 at 08:47:37AM -0800, Shawn O. Pearce wrote:
Show 10 quoted lines
> >>  - System resource cost we incur by having to keep 50 file
> >>    descriptors open and maintaining 50 mmap windows will reduce by
> >>    50 fold.
> >
> > I wonder how measurable that is (and if it matters on Linux versus less
> > efficient platforms).
> 
> It does matter. We know it has a negative impact on JGit even on Linux
> for example. You don't want 300 packs in a repository. 50 might be
> tolerable. 300 is not.

I'd love to see numbers if you have them. It's not that I don't believe it is slower, but knowing _how much_ is important when thinking about what kind of performance increase we are looking to get (which in turn impacts how much effort to put into the repacking).

-Peff
Previous: Shawn PearceNext: Shawn Pearce
Message 16 of 21 in “optimizing pack access on "read only" fetch repos”
  1. 0/2 optimizing pack access on "read only" fetch reposJeff King, Jan 26, 2013
  2. 1/2 fetch: run gc --auto after fetchingJeff King, Jan 26, 2013
  3. Jonathan NiederJan 27, 2013
  4. 2/2 fetch-pack: avoid repeatedly re-scanning pack directoryJeff King, Jan 26, 2013
  5. Jonathan NiederJan 27, 2013
  6. Junio C HamanoJan 27, 2013
  7. Jonathan NiederJan 27, 2013
  8. Junio C HamanoJan 27, 2013
  9. Shawn PearceJan 29, 2013
  10. Jeff KingJan 29, 2013
  11. Martin FickJan 29, 2013
  12. Junio C HamanoJan 29, 2013
  13. Jeff KingJan 29, 2013
  14. Junio C HamanoJan 29, 2013
  15. Shawn PearceJan 31, 2013
  16. Jeff KingFeb 1, 2013
  17. Shawn PearceFeb 2, 2013
  18. Duy NguyenJan 29, 2013
  19. Jeff KingJul 12, 2017
  20. Ævar Arnfjörð BjarmasonJul 12, 2017
  21. Jeff KingJul 12, 2017

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