LanderDB Performance

[vesellov]

Hi Max.
Seems like you have performance issure in zCoin.
I think it may work pretty slow if you have a lot users in network and lots of coins mined.
I am looking into landerdb.py now, seems like when you made some changes on database you always write all coins to disk every time, all entire db.db just get overwritten every time when new coin get mined.
Now imagine if have lots of miners in the network, so "relay" nodes will get a lots of new coins per minute and so finally they will reach some hardware write limit.
I would consider some improvements on landerDB so it can just update local file instead of rewrite it completely every time. I believe current solution is not really scalable but it is easy to fix in my opinion.
I am considering using zCoin in my code so probably I will do that for you :-)

[vesellov]

By the way, why you decided to not use sqlite3 ? I see you were using it in your past commits

[f-prime]

Boy, I haven't really thought about this project in a while. If I could redo certain things about it I would for sure. Sqlite3 has a locking problem that I couldn't solve at the time so that's why I created LanderDB, which is poorly designed as you have realized

[vesellov]

Okay Max, Seems like you are pretty busy with other things now and it is fine. 👍

I am also thinking about your broadcasting model. Looks like you sent everything to relay nodes and they should process the new coins and accept them. But if you have too much "normal" nodes and few relay nodes the whole network performance can also get in trouble, right ?

Also looking in the code I see you just have a loop on all relay nodes to send the data... what happens if all nodes in the network are working as "relay" nodes. Or say you have thousands relay nodes? Every iteration (every coin) can take really long time ...

Let me explain a little bit what I am looking for. In BitDust project I need to arrange a distributed storage to store public info about every node in the network. So every node can publish some service info and every other node should be able to read it at any moment of time. It must be safe, efficient and consume as much resources as possible. I believe a blockchain technology is just what I need.

As I understood zCoin is not real blockchain : blocks are not connected in a chain, right? But for me it is fine, I do not need a "currency", I need a storage. My idea is to attach a service data to zCoin record and "mine" it as a typical coin. So one node can publish own service data and all other nodes able to read it.

I am still going to use zCoin to build that solution but I see two main problems at the moment: landerDB performance and your broadcasting model.

Probably you are not very interested in that project any more, because I see that last commit was more than 2 years ago. But if you have a moment to think and talk about it I would be happy to contact. Any way, thank for that code! 👍