11. 09. 2019.

Who else could read your private & sensitive data stored in Cloud?

ZDNet has recently published an interesting article related to Public Cloud and GDPR related data jurisdiction – US Cloud act. Article is about digital sovereignty as more than half of European business with over 1,000 employees are using a public cloud platform, mostly AWS & Azure that dominate the Cloud market, IBM that dominates hybrid-cloud […]

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 […]

02. 09. 2019.

Cloning larger bootable HDD into a smaller one

This article is triggered by the real case when I have not only to clone larger (external) disk into a smaller one, but to keep cloned disk bootable as it’s source. The article is mainly reminder what I need to do, as I frequently need to prepare PoC (Proof of Concept) that requires to run […]

28. 08. 2019.

Installing Ubuntu on an external bootable HDD

In case you need to experiment with different OS from one that you already have installed, but don’t want to take a dual-boot approach to avoid possible corruption of your main disk, then keep reading this article – Installing Ubuntu on an external bootable HDD.   Although it is possible to run Linux along with […]

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 […]

14. 08. 2019.

Cloud – shared responsibility model, SaaS & Cloud security best practice

As industry is moving fast toward Cloud adoption, although not new (Amazon AWS platform was launched in July 2002), it’s no surprise that Cloud is still one of the hottest technologies around. Started with Simple Queue Service (first AWS service launched in November 2004), Cloud today is far away from the simple file sharing service. […]

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 […]

24. 07. 2019.

SaaS related GDPR, security and architectural issues

In the age of Cloud computing one of the most important challenges is how to keep security while moving your enterprise apps in the Cloud. In this article I’m going to explain what challenges you might experience if you are blindly follow all hypes from the tech industry.   Today enterprises are under tremendous pressure […]

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 […]