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Re: SVN Book Method for Splitting Repos doesn't work

From: Max Bowsher <maxb_at_ukf.net>
Date: 2004-12-31 01:07:22 CET

Patrick Smears wrote:
> On Thu, 30 Dec 2004, Max Bowsher wrote:
>
>> [...]
>> Any small overhead can become quite magnified when dealing with gigabytes
>> of
>> data, and if you want to restrict the available byte values to printable
>> ASCII, then the amount of space required to store arbitrary data will
>> increase by approximately a factor of 3.
>
> In general I agree 100% with what you're saying - but I'm puzzled as to
> where the factor of 3 comes in? I'd have thought that, with some sort of
> base64 encoding, you'd be able to store 6 bits of "real" data for every 8
> bits of "encoded" data - give or take some overhead for padding, sensible
> line breaks etc - so I'd have thought a figure of 30-40% extra would seem
> more likely... playing with uuencode would seem to confirm this:
>
> % head -c1000000 /dev/urandom | uuencode - | wc -c
> 1377800
>
> Indeed, I'd have thought that storing each "real" byte as two hex digits
> would only double the output size... What am I missing here?

I think I was hallucinating my mathematics :-)

Max.

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Received on Fri Dec 31 01:10:48 2004

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