03. 12. 2019.

Oracle RAC in the AWS Cloud – performance testing part I

Last time, all components (network, storage, Grid infrastructure…) are prepared for Oracle database RAC installation with a minimal time and effort thanks to Flashgrid’s wizard which, behind the scene, is using Cloud Formation template to setup everything, including installation of all necessary patches available at the time of installation.   You can find more on […]

21. 10. 2019.

Performing stress test against Oracle database that is running in a Cloud

Today majority of enterprises are moving or at least considering moving some load into the Cloud. What you need to be aware in such case, system requirements for a Cloud load are quite different when comparing with on-premises, mainly due to many new moving parts that are not present within classical environment such as sharing […]

05. 09. 2019.

Reducing CPU consumption and Oracle licenses by fixing context switching in Oracle Db

Context switching is one of the most overlooked topics when tuning the Oracle database, as you can’t simply see it directly (e.g. “context switching” wait event doesn’t exist). Instead you should use indirect approach  (through the increased CPU consumption), as it’s recorded as a CPU wait event. Context switching what it is and what impact […]

23. 08. 2019.

Oracle single-threaded CPU performance reference test, native compilation and performance improvement after upgrading your database

In this article I’ll provide a very simple way of how to test Oracle CPU single-thread performance.   Apart from that, I’ll cover performance boost you might expect when upgrading your server (especially CPU), expected performance boost when performing simple upgrade of the Oracle database, and issues and workarounds related to native compilation of PL/SQL […]

28. 07. 2019.

How to quickly perform REST API performance test

REST API interface is dominant way of machine-to machine communication because of its flexibility, performance, simplicity and lightweight.   Recently I had to perform a quick performance test to check if response time of one application is in line with SLA (Service Level Agreement). Such performance tests are particularly important in case of SaaS architecture […]

22. 07. 2019.

Oracle database benchmarking by using CALIBRATE_IO

CALIBRATE_IO is yet another popular database simulation/stress test utility, mainly used to perform IO benchmarks.   Procedure, that is part of DBMS_RESOURCE_MANAGER package, will generate read-only workload made up of 1 MB of random of I/Os to the database to determine the maximum number of IOPS and MB per second. You can save the following […]

17. 07. 2019.

Implement High Performance Computing tools to test cluster stability

There are many benchmark testing tools that are focusing on various fields of a cluster like computing capabilities, energy efficiency, data & storage, memory etc. In this article I’m going to use Somberero – High Performance Computing tool suitable to run a test against your home PC or cluster of supercomputers. Sombrero is particularly useful […]

17. 05. 2019.

How to change the execution plan without changing the code in Oracle 10g

Recently I had an interesting case when I’ve been asked how to change the execution plan of one complex query without changing the code. I’ve already had a lecture with similar title at 2012 in Oracle User Group Conference – more details you can find at the following link: How to change the execution plan […]

08. 05. 2019.

Processing billions of records with Python & Oracle

Suppose you want to analyze data set by using your favorite tools (Pandas/NumPy). By reading my previous article: How to efficiently load data into Python from the Oracle RDBMS , you should realize how important is to do as much of data processing at the database SQL engine layer to get out dataset suitable for […]

23. 04. 2019.

How to efficiently load data into Python from the Oracle RDBMS

Python has many different ways to fetch the data needed to do some processing. Although majority of examples you can find around are using CSV file load, fetching a data from the database is still the most common way in practice. For all tests I’ll use SALES table from the Oracle SH sample schema. 1. […]