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 _______________________________________________ Opensim-users mailing list Opensim-users@opensimulator.org http://opensimulator.org/cgi-bin/mailman/listinfo/opensim-users