PGConf.Russia 2022

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.

During my career, I've seen a lot of code, and very often I faced inaccuracies in handling dates and times. Sometimes the parties got discrepancies in the monthly reports due to such inaccuracies; or daily reports were different for Moscow and SFO, etc. I wouldn't call it a serious problem, but it's annoying and time-consuming. In all cases, such issues occur because of neglectful handling of dates and times. In my presentation, I will discuss how we can avoid it.

We'll talk about the ways to change the database records without updates. To do this, we'll explore what's going on at the lowest level and see what can happen if we make changes in data files in different operation modes.

My talk covers PostgreSQL infrastructure in Ozon: - how do we tune virtual machines (KVM); - which version control system we have created; - which drivers we make and how it relates to fault tolerance and load balancing; - how do we make "hot" upgrades for the parameters of our virtual machines.