There are many research papers on problem of scalability of blockchains:

Just as an example : An Overview of Blockchain Technology: Architecture, Consensus, and Future Trends

However, (usually by some companies which uses blockchain technology), it's mentioned that one of the advantages of blockchain against centralized relational databases, is scalability.

Just as an example : WePower White Paper.

Quote from this white paper:

Relational databases are adequate in many applications and situations. However, sustainability and scalability are limited with these databases. From the perspective of sector transformation in trading and digital infrastructure creation, transforming energy production to 100% renewable, the answer was to utilize a public blockchain.

Is it a correct proposition?

  • blockchain algorithm can't be scaled because it was designed to be serial at core. poor are the people who are still looking for ways to scale, it is an impossible thing to do.
    – Nulik
    Aug 22 '18 at 13:22
  • @Nulik Thank you, what do you mean by to be serial at core ? Thanks
    – Questioner
    Aug 22 '18 at 14:13
  • 2
    I mean it is not parallel. Just like a processor in Von Neumann architecture. If you noted last decade the speed of the microprocessors decreased due to the speed of light limit. Now the only way to scale is to rewrite the software for parallel architecture. Same thing with the blockchain. You must parallelize tasks, but with the blockchain, the serialness of the processes is the main feature. It is because of this serial property that the blockhain technology has become so reliable. A hash of a hash of a hash of a hash .... you can't parallelize this.
    – Nulik
    Aug 22 '18 at 15:52
  • @Nulik blockchains are absolutely parallelizable, that's mainly what sharding is doing. On top of that, parallel processing of transactions is easily possible within blocks if transactions were required to name a list of accounts they touched. If the list of touched accounts don't overlap for two transactions, then the two transactions can be processed in parallel.
    – natewelch_
    Sep 4 '18 at 15:06
  • @flygoing I would be very careful with the absolutely word , in your place. Transactions already say the accounts they are touching, it is the From and To field of the TX. Then, how do you derive the list of parallel transactions? By a SERIAL process. See it? You can't escape serialness. After you process the transactions, you will have to tie up the work that has done by creating a hash on all touched accounts, thats another SERIAL process. If you have network latency, your serial algorithm is going to be dead slow. That's what I am talking about
    – Nulik
    Sep 4 '18 at 15:45

This article addresses current scalability issues of the blockchain and potential solutions for those issues.

  • Thank you, but my question is which one are really more scalable ? Thanks
    – Questioner
    Aug 22 '18 at 14:15
  • 1
    RDBMS is more scalable than blockchain. The blockchain is definitely having storage and processing limitations. Aug 22 '18 at 14:59
  • So you are not agreed with the quote from that white paper in my question? Thanks
    – Questioner
    Aug 22 '18 at 15:02
  • Yes, I do not agree with the quote from that white paper. Aug 22 '18 at 15:39

Not the answer you're looking for? Browse other questions tagged or ask your own question.