PgConf.Russia 2019

This talk will represent a new platform of Distributed Control System for Nuclear Power Plant operation. Participants will learn about control system for very complicated automation objects. In a hard real time node more than 150 special subsystems are operating in order to control various technological processes of nuclear power plant (NPP), such as reactor control system for more than 1000 MW power unit with a turbine weighing more than 2000 tons. More than 100K of data gained from sensors are resulting in up to 500K of parameters representing 5 branches of physical processes: neutron kinetics, hydrodynamics, chemistry and radiochemistry, and physics of strength. Deviations may cause the whole system to become a huge DDoS source made of useful diagnostic information which is always much larger than the network and hardware are capable to manage. This may lead to normal operation failure. The talk will reveal the approaches to solve the issue.

You will learn about hardware and software architecture of such systems, about backup and replication, data redundancy and technological diversity. How to manage high loads, what is QoS, and what will happen in case of normal operation system failure, as for example was at Fukushima. But, hey, there should be a talk about coding! So, no SSD and HDDs, only InMemory, data structures from tens of millions of elements, and forget about processor cache as it does not work. Imagine your newest 4-generation Xeon has lost all the advantages and turned into a "pumpkin", so let's roll up your sleeves and examine timings, synchronicity, and try to make the most of your hardware, discovering the weakest link from processor, operating system and a network.

IIn the world of programming, the creation of source code for databases "procedural extensions" is something solitary. Most DBMS offers procedural languages and "stored procedures" to create procedural extensions. In Postgres the number of supported procedural languages has already exceeded a dozen.

Traditionally, stored procedures have many applications: it is difficult to resist the attraction to perform a data operation directly in the storage, especially in the Enterprise development. This approach quickly leads to the spreading of the business logic and dramatically increases the cost of support and development of the system as a whole.

The life cycle of stored procedures makes it difficult to use standard Change Management tools and practices. It is necessary to adapt the operations upon the stored procedures to the standards of Change Management, yet staying within the comfortable development practices.

We'll look at the typical tasks of the procedural extensions development and discuss the solutions we are implementing in the Xobot IDE.

One of the most soft after features of Postgres v10 is logical replication. In this presentation we will cover what Logical Replication is, how it compares to Binary (Streaming Replication), how Logical Replication works, configuring Logical Replication, Logical Replication limitations, gotchas, security and management. We will also discuss potential deployed architectures with Logical and Binary Replication and some neat features of the underlying technology.

At the end of this presentation an attendee with a reasonable understanding of how to manage Postgres will be able to configure Logical replication for use.

Several real cases from those who stopped the migration to PostgreSQL.