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Re: [PATCH] pack-bitmap: do not use gcc packed attribute

From
Vicent Martí <tanoku@gmail.com>
Date
Aug 5, 2014, 18:38 UTC
Message-ID
<CAFFjANRwnd4u1Axs64xZNvc1kHynjswX_t4pS3EjBsTsZP0Y7w@mail.gmail.com>
In-Reply-To
<53DFDCD2.2090803@gmail.com>
On Mon, Aug 4, 2014 at 9:19 PM, Karsten Blees <karsten.blees@gmail.com> wrote:
> This raises the question why we read via mmap at all

The first version of the pack bitmap format I wrote for GitHub was 50% faster to load than this one because it was designed to be mmapable. Eventually we moved to the JGit-compatible bitmap format (because I get paid a lot of money to do as I'm told -- not because of some inherent benefit of the JGit format), which needs to be read sequentially, but I never bothered to change the mmap reading code.

I believe your patch makes a lot of sense -- at this point we could as well remove the mmaping altogether and read the file sequentially.

Cheers, vmg

Previous: Karsten BleesNext: Jeff King
Message 7 of 12 in “struct hashmap_entry packing”
  1. Jeff KingJul 28, 2014
  2. Karsten BleesJul 29, 2014
  3. Jeff KingAug 1, 2014
  4. pack-bitmap: do not use gcc packed attributeJeff King, Aug 1, 2014
  5. Jeff KingAug 1, 2014
  6. Karsten BleesAug 4, 2014
  7. Vicent MartíAug 5, 2014
  8. Jeff KingAug 5, 2014
  9. Karsten BleesAug 6, 2014
  10. Junio C HamanoAug 6, 2014
  11. Karsten BleesAug 4, 2014
  12. Jeff KingAug 5, 2014

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