Improve blocks processing efficiency

[4miners]

Block processing is not so efficient and logic is not perfect currently - because of that there are many possible issues and bottlenecks. Since it prevents us from expanding network and features - time to improve that.

• SQL performance & flexibility SQL performance & flexibility #482
  • Review queries and test their performance, find slow queries/views
    • Improve performance for existing queries/view (if needed)
  • Review data types performance & consistency

Connected issues:

• Node forked and didn't rolled back Node forked and didn't rolled back #324
• Syncing from scratch randomly slows down Syncing from scratch randomly slows down #352

Removed tasks:

• Review use of sequences (db, balance) Review use of sequences (db, balance) #538 (Cancelled)
• Refactor round logic Refactor round logic #543 (Cancelled)
• Redesign accounts ledger Redesign accounts ledger #544 (Cancelled)
• Rewrite transaction pool Rewrite transaction pool #561 (Cancelled)
• Integrate new accounts ledger and transaction pool Integrate new accounts ledger and transaction pool #972 (Cancelled)
• Improve blocks related logging Improve blocks related logging #539 (Cancelled)

Previously connected issues:

• Achieve atomic block save Achieve atomic block save #302
• Refactor blocks module to submodules Refactor blocks module to submodules #534
• Reload sometimes cause blockchain rebuild Reload sometimes cause blockchain rebuild #411
• Why is mem_round flushed twice while finishing a round Why is mem_round flushed twice while finishing a round #216
• Improving network synchronisation - decentralised blockchain snapshots Improving network synchronisation - decentralised blockchain snapshots #235
• Improve block replication Improve block propagation #333
• Add information about slot to blocks Add information about slot to blocks #348
• Tracking of missed blocks Tracking of missed blocks #349
• Networks lose stability when broadcasting transactions Networks lose stability when broadcasting transactions #339
• Round arithmetic is using standard Math functions Round arithmetic is using standard Math functions #447
• Review block verification logic Review block verification logic #459
• Consistency when dealing with timestamps Consistency when dealing with timestamps #448

[karmacoma]

@4miners I've revised the above mother issue with links to the associated child issues, plus marked our current progress.

[karmacoma]

Nested points are now stored in child issues I've opened if not already.

[Isabello]

#541 and #459 have been reopened and require some additional work to be performed.

[karmacoma]

Issue #459 closed. #541 remains open for completion.

[karmacoma]

Detached #302 from this issue. Therefore work complete.