2011/5/13 Robert Norris <rw_nor...@hotmail.com>: > > >>The default for tile age seems to be 30s. This seems way too short. >>While someone actively mapping in OSM might want to reload, it seems >>like map tiles are relatively static over that kind of timescale. I >>have set the tile age to 604800s (1 week). It seems rude to OSM to >>recheck tiles more often than once a day, or maybe once an hour. > >>For terraserver DRG and imagery, 1 week is perhaps too short - those >>bits are quite static. > >>What's the motivation for 30s? Would anyone object to changing it to 1 >>week? > > No idea why it was set to 30. Presumably because that's better than 1 second! > > I thought the default was changed, but double checking shows it was just > upping the max allowable value in gui preference. > > Maybe the value should be shown in days/hours. > I mean how useful is it to set it to 54320 seconds? - what does that even > mean! > > Agreed 1 week is much better, although personally I use 1 day (86400s) which > might be better for OSM type usage.
Please, note that such SMALL delay was coupled with the ability to check the status of files on remote without downloading it. So, theorically, the load on server is quite reasonable. But it seems our implementation of this part is perfectible. Other note: due to "theory" of observation, the refresh frequency should be more than twice the effective refresh on server. The better example for this, is the case of a clock: the UI part should use a timer less than half a second (for example 0,4 second) in order to ensure the clock always displays the right value. So, if you think tiles are refreshed once a day, you have to set a value less than half a day. Example: with a 1 day delay, if tile is changed in 1 day + 1 second, you will wait 2 days before having the fresh tile. Other note: how work web browsers about this? What is the delay used? > Another alternative could be to have another tile age for 'non-volatile'* > maps such as mentioned: terraserver, bing, etc... > *better name needed - stable? > Which would default to something like a month. Why not only zero, in order to only alow manual refresh? -- Guilhem BONNEFILLE -=- JID: gu...@im.apinc.org MSN: guilhem_bonnefi...@hotmail.com -=- mailto:guilhem.bonnefi...@gmail.com -=- http://nathguil.free.fr/ ------------------------------------------------------------------------------ Achieve unprecedented app performance and reliability What every C/C++ and Fortran developer should know. Learn how Intel has extended the reach of its next-generation tools to help boost performance applications - inlcuding clusters. http://p.sf.net/sfu/intel-dev2devmay _______________________________________________ Viking-devel mailing list Viking-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/viking-devel Viking home page: http://viking.sf.net/
