PGConf.Russia 2022

Every DBMS stores its data on a hard disc, so you may face a situation when your data on disc gets corrupted. This can happen due to a controller failure, logical or physical data corruption; there are also other reasons. If it is just the index file that gets corrupted, the index recreation command will enable you to restore data consistency in your DBMS. If a table file or a file of a system section gets corrupted, data restore is impossible. In this case, you need to invent workarounds. You can try to restore this data from backup files, copy it from the corrupted table, or find another way to solve this problem. In this talk, we'll tackle several cases of data corruption on disc and describe the options for restoring the data from the corrupted tables.

As opposed to in-memory DBMSs, traditional disc database management systems have an inherent physical limitation. It's their storage system which is by several orders of magnitude slower than CPU operation memory, even in the case of All-Flash NVM. It becomes especially critical for the development of business analytics apps and OLAP scenarios on disc DBMS. We will consider a number how-tos for improving the performance of traditional DBMSs, and then offer a new storage-centric approach to hardware-based speed-up for disc DBMSs.

In June 2020, AlfaStrakhovaniye was obliged to use RSA 2.0 government services along with other insurance companies. It was the only way to sell car insurance in Russia. AlfaStrakhovaniye is a leader in car insurance, and its applications degraded under the pressure of calls. It wasn't planned. Postgres used a huge amount of CPU and memory. Nobody could tell what was going on. Degradation started and stopped for no reason. Dev Team and Postgres Pro experts solved that problem. MyBatis in Java services was the killer. Our story is about the development of applications for heavy workloads and technical ignorance while using frameworks.

Our talk reviews the modern tools for administering PostgreSQL. It also covers the DBMS's performance bottlenecks and provides approaches to resolving the related issues. The presentation tackles the problems that occur while Oracle to Postgres migrations including the following: performance tuning tools (the analogues of AWR and ASH); monitoring tools (the analogues of Cloud Control); ensuring high availability and reliability of the database (grid infrastructure analogues); known "database performance bottlenecks"; an overview of options for technical support options SLAs.