On Mon, Aug 27, 2018, at 1:47 PM, Haravikk wrote:
> 
> > On 27 Aug 2018, at 09:57, Ethan Gardener <eeke...@fastmail.fm 
> > <mailto:eeke...@fastmail.fm>> wrote:
> > 
> > On Mon, Aug 27, 2018, at 8:06 AM, Haravikk wrote:
> >> 
> >>> On 26 Aug 2018, at 15:05, Ethan Gardener <eeke...@fastmail.fm 
> >>> <mailto:eeke...@fastmail.fm>> wrote:
> >>> 
> >>> However, everything I've ever learned about databases says that it's a 
> >>> bad idea to just look at the cost of the disks.  The cost of *accessing* 
> >>> the data (with acceptable performance) goes up exponentially with the 
> >>> size of the dataset.
> >> 
> >> This shouldn't be the case; any properly indexed database should have 
> >> roughly constant, or at worst logarithmic, access times for data.
> > 
> > *sigh* "Logarithmic" is another way of saying "exponential'.  It is not a 
> > trivial matter unless the data set is comparatively small.  In asking about 
> > these things, I'm particularly thinking of InWorldz, where asset data was 
> > growing at a terabyte a month.  Not small.  
> 
> Logarithmic complexity isn't the same as exponential complexity, in fact 
> it's the opposite; logarithmic complexity plateaus as the search space 
> increases, meaning it effectively becomes constant time, an algorithm 
> with exponential complexity would grow by a power of the search space 
> size (e.g- the search time might quadruple each time the search space 
> doubles in size). See here:
> https://en.wikipedia.org/wiki/Logarithmic_growth 
> <https://en.wikipedia.org/wiki/Logarithmic_growth>
> https://en.wikipedia.org/wiki/Exponential_growth 
> <https://en.wikipedia.org/wiki/Exponential_growth>

Oh I'm sorry, I was reasoning from a bad premise.  I later remembered I 
regularly use a program which has logarithmic search time.  (It's not even a 
database, it's the grep command in Plan 9 from Bell Labs.)  Thanks for your 
explanations.

This leaves the problem as an even bigger puzzle to me, I don't think I can 
even begin to reason on possible causes.  Perhaps I should just leave it at 
this, as I'm reducing my involvement in virtual worlds for personal reasons 
anyway.  (I'm taking up programming instead.  Maybe in a few years, I'll have 
something to offer. :)  

-- 
The lyf so short, the craft so long to lerne. -- Chaucer
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