Kirill Kryukov wrote:bob wrote:
It is one thing to do 7 piece files, it is another thing to store them, and yet another thing to use them in a live search. I am not sure technology is "there" today, both from a size and a speed perspective. And I am not sure they are ever going to be really useful, other than for specific endgame studies.
Thanks to Arpad for bringing it up here.
I think it's clear now that many people find 6-piece tablebases useful. Some for playing, some for composing, many more for analyzing. Many choose to have only part of the 6-piece set, so the size of the whole set is not too important. So, if we could already have KRPPKRP, or KPPPKPP now, how many of us would refuse? Certainly you'd find space on your hard drive for those table, if they were available.
Hard to say. Those types of files (KPPPKPP) are on the order of 8tb per pair before compression assuming 1 byte for DTC rather than DTM Double that for DTM. That's a daunting thing to store, to download, to probe / cache in a search, today. How many terabytes do you have sitting around?
Personally I believe the technology is already here for producing and sharing the whole 7-piece set. The key is to not try building all tables by yourself (traditional approach), but involve the community. So developing the efficient infrastructure for this project is as important as the generator itself.
Today's internet backbone, even if you can get on the 1gbit backbone locally, is not up to this task. This is not a simple distributed SETI online project. The data is computed sequentially and you have to finish one pass before starting the next. Not so easy to distribute, particularly outside a lab with a really good network like Infiniband or 10gbit.
If the key specs for the generator and the infrastructure are designed by the community, and if sufficient motivation is provided for developers to comply to those specs, the end result will be practically a paradise on earth - a complete 7-piece solution available to anyone at any time. How much of this will come true is up to the community, which means all of us.
The usefullness is greatly limited when you have to go across a network to access the data. You are not going to use that in a search, for certain.
Note. The infrastructure should provide support for three tasks: 1. Distributed generation of the tables. 2. Distribution of the completed tables. 3. Remote probing. So those who can't store the local copy of the tables will still have access to the whole 7-piece solution, just at a much slower speed.
Note 2. When building a DTZ (or DTZ50) table, the sub-endgame tables can be in WDL (or WDL50). This means that when the whole 4-vs-3 set is solved in WDL, you can suddenly build KPPPKPP in DTZ without building any other DTZ first. This property of DTZ will significantly accelerate our path to the useful tables.