From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Gummerer <t.gummerer@gmail.com>
Subject: Re: Index format v5
Date: Thu, 3 May 2012 22:36:07 +0200
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To: Ronan Keryell <Ronan.Keryell@hpc-project.com>
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On Thu, May 3, 2012 at 8:21 PM, Ronan Keryell
<Ronan.Keryell@hpc-project.com> wrote:
>>>>>> On Thu, 3 May 2012 19:25:12 +0200, Thomas Gummerer <t.gummerer@g=
mail.com> said:
>
> =A0 =A0Thomas> I have been drafting the Version 5 of the index format=
 over
> =A0 =A0Thomas> the past few days with the help of Thomas Rast, Michae=
l
> =A0 =A0Thomas> Haggerty, cmn and barrbrain on IRC. It will save with =
prefix
> =A0 =A0Thomas> compression on the path, and using a crc32 over the st=
at
> =A0 =A0Thomas> data, instead of the full data, since it is only used =
for
> =A0 =A0Thomas> checking if the file is changed. (Thanks Michael Hagge=
rty
> =A0 =A0Thomas> for this hint. Unless we are missing something this wi=
ll
> =A0 =A0Thomas> save another ~4 MB on the Webkit index.
>
> Great!
>
> But I wonder whether it may not worth to investigate a 64-bit version=
 for
> the offsets and so on, just in case...

64-bit versions of the offsets were taken into consideration, but curre=
ntly
the Webkit index (the largest I know) has a size of 26 Mb, which is
reduced to about 15 MB or less with the v5 format. With 32-bit we can
address 4GB, which is about 266 times the Webkit index. Therefore there
probably is no use for 64-bit offsets in the years to come.