On Monday 03 December 2001 07:26 pm, you wrote: > I could be wrong, but I think this is equivalent or similar to a scheme > that was proposed a while ago (perhaps by me - I can't recall). > > This stuck with the current DBR system, but when today's edition didn't > exist it would try yesterdays, then 4 days ago, then 8 days ago, then > 16, exponentially searching backwards. When a page is found it > exponentially searches forwards in a similar manner, then backwards, > forwards, etc etc (sorry not a clear explanation, I will leave it as an > exercise for the reader to fill in the details). In common with your > suggestion, this should find the most recent edition in logarithmic > time. > > Ian. >
Searching 1, 2, 4, 8, etc. inserts ago wouldn't work as well. For the Binary Tree DBRs, root branches will be requested more often and then become more reliable. If one of the lower leafs becomes inaccesible, the next-highest root would be more relaibily accessible. This is because of the required traversal methods of the binary tree. Also, a power of two lookup might not find the most recent one if it misses a day. Binary trees handle that without too much overhead. The Binary tree automatically handles change in update frequency. A user could insert two versions less than a second apart without problem, or leave it for a year without updating. It can scale down the time interval infinitely small too. Scott Young _______________________________________________ Devl mailing list Devl at freenetproject.org http://lists.freenetproject.org/mailman/listinfo/devl
