19. 06. 2022.

How to speedup pooling queries from the Oracle database

This post is a kind of extension of my previous post named “How to index only rows of interest” which can be found on the following link: https://www.josip-pojatina.com/en/how-to-index-only-rows-of-interest/   Having issues with pooling queries are very common in old, SOA based architectural style, where ESB (Enterprise Service Bus) are throwing the same query again and […]

22. 10. 2021.

When visual tool for monitoring appears to lie

A few days ago I was asked to take a look at two queries that shows up among the top queries in the Oracle SQL Developer instance viewer. I’ve extracted two statements that are relevant for this case.     The select statements for both records are almost identical:   From the SELECT statement it […]

18. 08. 2021.

Functional monitoring of Microservices architecture by using Apache Superset

Many of you who have started to develop modern apps by using Microservices approach, have already learned that development tools, debuggers, performance monitoring and tracing lag behind the desired architecture. Situation is even worse when it comes to functional monitoring, where your goal is to find out what is going on with your system from […]

05. 06. 2021.

Missing columns in PrestoSQL

One of the first issues when starting to use PrestoSQL distributed query engine is related to missing columns of certain data types, especially numeric and all variants of date. This issue is usually because of missing precision at the data source, which is not only one of the most common, but also one of the […]

16. 02. 2021.

Postgres monitoring with Percona PMM

For those who are coming from Oracle world, the best alternative database is probably Postgres, because of many similarities between those two Db engines (data types, tablespace concept etc.).   However, one of the first thing you want to do is to grab a full control over what is going on in your database. If […]

21. 01. 2021.

Kafka & TCP Retrans Error rate

Recently I had an interesting case where in the data pipeline I’ve found duplicate messages in the Kafka topics. Duplicate records in Kafka topics might appear for many different reasons, but most of them you can find only those related to the Kafka settings (especially those related to the Kafka settings). In this article you […]

06. 12. 2020.

Bashtop – future of the terminal Linux monitoring

Although the idea of the original top utility is follewed in many similar utilities for terminal based Linux monitoring, till now I’ve been using Htop, atop (which can monitor GPU on top of CPU/Mem/Net/Disk) and Nmon to do a job (later one, called „Topas on steroids” is ported from AIX to Linux). Quite recently I’ve […]

06. 10. 2020.

Perfect case for NoSQL database

On many sites where I’ve been involved in troubleshooting and performance tuning, I can find usage of wrong technology for a wrong use case. Usually client technology experts are keen with some new features of some technology and want to solve all kind of problems by using it. In practice, new features are added to […]

24. 09. 2020.

How to setup Adobe Flash Support in Browser for Linux

Some vendors still relies on Adobe Flash for rich web contents. One such example is Oracle, where you can find that all tuning reports are generated by using Flash. Even Oracle Enterprise Manager Grid, main Oracle monitoring tool still uses Adobe Flash to generate its content. If you are on Windows, you can use Internet […]

10. 05. 2020.

Customer experience on Oracle Db – One metric to rule them all

Over the years I’ve found that almost every enterprise monitoring software I’ve been working with so far (and there are a few dozen of them), put extensive load on targets under the monitoring. While one monitoring tool brings extensive hard parsing on its targets, another one calculates free space for each tablespace in a very […]