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 Hello. I've set up T@H yesterday and noticed a small efficiency problem with a forked setup. tilesGen.pl starts with a single, simple z12 256x256 tile and goes towards more complex pictures. This leaves it with a *single* z17 inkscape trying hard. It would be much more efficient if z17 was the first zoom levevel to deal with because (lets assume a spherical cow) Let Fork equal 2. Let time(z_n)=4*time(z_{n-1}) If time(z_12) = 1 then time(z_12..z16) = 341 and time(z17) = 1024 If the first thread starts with z17 then the other can do all other levels in parallel If time(z_n) = 2*time(z_{n-1})    then time(z_12..z16) = time(z17)-time(z_12) -- Łukasz Stelmach _______________________________________________ Tilesathome mailing list [hidden email] http://lists.openstreetmap.org/listinfo/tilesathome
 Am 07.02.2011 12:06, schrieb Łukasz Stelmach: > Hello. > > I've set up T@H yesterday and noticed a small efficiency problem with a > forked setup. tilesGen.pl starts with a single, simple z12 256x256 tile > and goes towards more complex pictures. This leaves it with a *single* z17 > inkscape trying hard. It would be much more efficient if z17 was the > first zoom levevel to deal with because (lets assume a spherical cow) > > Let Fork equal 2. > Let time(z_n)=4*time(z_{n-1}) > If time(z_12) = 1 then time(z_12..z16) = 341 and time(z17) = 1024 > > If the first thread starts with z17 then the other can do all other > levels in parallel > > If time(z_n) = 2*time(z_{n-1}) >    then > time(z_12..z16) = time(z17)-time(z_12) > Short answer: It makes sense to run the z17 thread alone, because it's not cpu but RAM bound. -- Dirk-Lüder "Deelkar" Kreie Bremen - 53.0901°N 8.7868°E Ceterum censeo Carthaginem esse delendam. _______________________________________________ Tilesathome mailing list [hidden email] http://lists.openstreetmap.org/listinfo/tilesathome signature.asc (270 bytes) Download Attachment
 On Mon, 07 Feb 2011 13:59:05 +0100, Dirk-Lüder Kreie <[hidden email]> wrote: > > If the first thread starts with z17 then the other can do all other > > levels in parallel > It makes sense to run the z17 thread alone, because it's not cpu but RAM > bound. You don't want to run z17 rendering in parallel to anything else, believe me :-). If there are problems, this is where they will occur. Sebastian _______________________________________________ Tilesathome mailing list [hidden email] http://lists.openstreetmap.org/listinfo/tilesathome attachment0 (203 bytes) Download Attachment