Sunday, May 1, 2016
All Hands Meeting
Sunday, March 13, 2016
Sunday, January 31, 2016
Sunday, January 24, 2016
As simple as LEGO
Sunday, January 17, 2016
Bugs at the bar
Friday, January 1, 2016
After Lunch Atop a Skyscraper
And what does this have to do with TESTING? Nothing, but these 11 testers mark my QA team spread all over the world, and although they are sitting high above ground, they've got wings and I hope they use them to overcome all following challenges and ups and downs we may face in this new year 2016.
Thursday, December 31, 2015
Performance Testing applied
Tuesday, December 22, 2015
Early Hotfixes
A beautiful exemplar of "ugly workarounds" from the Sixties was presented to me just yesterday. I took a shot with my camera and I just couldn't resist posting it here...
Tuesday, December 15, 2015
Power Breakdown in Zurich
Thursday, October 15, 2015
How developers see their code
The developer stated: "by looking at the code, I know that it works".
Actually, he wasn't at fault, but it was kind of amusing for me to see how different developers think compared to software testers.
I don't believe in code-snippets that I see on a piece of paper or checked-into some source code management system. I want to see this thing run, fly and rock before I make a statement that I like what I have seen. Besides, it also reminded me to another developer statement I've accidentally witnessed many many years ago and I will never forget that phrase which was: "I haven't tested it, but the implementation looks great".
To be honest, I can't tell here whether the developer said that to himself to blow his own horn or whether he was talking to another developer to compliment on his work.
However, after all these years being involved in many testing projects and having developed software myself long time ago, I have always marveled developers' ability of innocent look at their code like they constructed a beauty, only to learn a little later from a critical thinker that either half of it is missing or not working as intended. When I was developing software my own, I was always uncertain whether I did the right thing and I asked the customer several times, if this is really how this thing should work. But that was 20 years ago and we didn't have any testers at that time who served as a protective barrier between development team and customer. The customer was coming to us - developers - every six weeks to tell us where we were wrong. We faced these customers directly. Maybe that made a difference.
Friday, July 31, 2015
Cross delivery
I worked several hours on this cartoon and I prepared not less than 10 different drafts which I all abandoned because I was not happy with the characters I chose to represent the code pieces. l I finally decided to take that little triangle from Java. I kept a few of the drafts and decided to upload the last two of them so you can see how things develop.Thursday, July 2, 2015
Friday, May 15, 2015
Finding the right moment for your tests
Inspiration:
On February 21, 1990,
commander Hans Lutz, carried out a system training on the Saab 340 aircraft
type with a copilot onboard. The discussion turned to the procedure of
remedying a landing gear retraction fault. The commander was of the opinion
that on the ground, with the landing gear under load, the function of the
retraction mechanism was interrupted. Contrary
to the commander’s assumption, the hydraulic pumps began to work and the
retraction process could not be interrupted. The aircraft impacted on the
ground and was a total loss.
Source:
https://www.sust.admin.ch/inhalte/AV-berichte/1793_e.pdf (chapter 1.5.1.4.2)
Wednesday, May 6, 2015
Wednesday, February 11, 2015
Friday, February 6, 2015
Foreign Particles in the Code
Why is it always the testers who "fail" when a bug is going live and why is none ever asking the developers why they introduce bugs without asking the testers upfront for permission to ship bugs?
Tuesday, January 20, 2015
High IQ cat
All of us had to play this weird online game which - we believe - should either measure our IQ, gather information on how we work or how we deal with pressure. None knew! We never received the results; no feedback. All we saw were points achieved without knowing what is good or bad. We did not even get any answers to bugs we reported while playing the game.
One of the team-mates made the game play with itself. No human interaction, simply doing nothing, no keyboard clicking or whatsoever and he disappeared into the cafeteria. That person achieved the most points of all.
What does it tell us? That game was either crap and with it of course all the results that were collected from the employees or there is something we just didn't know. We will never know.
Sunday, January 11, 2015
Saturday, November 29, 2014
Empire State Building built with MINECRAFT
Watch video here:
Empire State Building built with MINECRAFT
Friday, November 7, 2014
Sunday, August 31, 2014
Thursday, March 27, 2014
Wednesday, February 26, 2014
Compatibility Challenges
Thursday, February 20, 2014
Robots Wedding
Friday, February 7, 2014
Arctic Tennis
BTW, I was asked whether it was by purpose that I took a FEMALE penguin sitting on this tennis ball. Not really. The truth is, first I used a male penguin but then I suddenly questioned whether male penguins do hatch eggs. I wasn't quite sure but I still had in my mind that male and female are taking turns between each other. At that time it was already too late to verify (01:00 am) and I was too tired to do proper investigation. In the meantime I verified it. Both penguins are breeding the eggs. While one is hunting for food, the other takes over the breeding job.
Wednesday, November 27, 2013
Robot Breeding
Thursday, October 31, 2013
New App in town
BTW, please excuse the grey shade in the last two cartoons. This is an ugly boring bug within Google's Blogger tool which introduces a grey background into all uploaded pictures even though whey are supposed to be clearly white.
There are some comments from other bloggers who suffer of the same problem.
Wednesday, October 16, 2013
Waterproof
Thursday, May 9, 2013
Dumbo talking
Sunday, March 31, 2013
Off the Scent
Monday, February 25, 2013
Risk Management
Sunday, December 23, 2012
End of the World
Best wishes Torsten
Friday, November 9, 2012
Performance Testing
How to do performance testing
What a test manager is interested before going live is often this: "Does the system respond fast enough and still accurately if there are 10,20,30 or more users's working in parallel?
Performance testing tools provide you the ability to develop scripts that fire scripted scenarios and measure their response time when executed isolated or all together using these ramp up numbers. Often, problems already show up with a much smaller number of parallel users using the system. Before you buy expensive experts, solve these problems first. Write either one or more simple Selenium UI scripts or some API-tests like REST/SOAP, build an endless loop around it and ask some colleagues whether they are willing to run the scripts from their workstations. Then find a free workstation where you can do manual testing in parallel to feel how it is not to be alone anymore.
If that reveals no bugs, move to the next stage and hire experts who can do the ramp-up as explained in the first sentence. Usually you should come up with 4-5 typical scenarios which cover at least 1 read, 1 update, 1 create and probably 1 delete operation. Not more, because scripting and providing test data for these scripts can be the most time-consuming and costly part in a performance test session. Also note, that a typical distribution of user's actions is 90/5/5 (90% read, 5% update, 5% create) or 80/10/10 or similar.
When using a professional performance testing tool (or working with an expert company), make sure you test the different scenarios in isolation. That means, let's test what happens if you have 10,20,30 or more users only doing read requests, then do the same only for update and yet another set only for creation. In most cases you will learn that a high number of read requests are nearly noticeable while it is often a different story once you test one of the other scenarios. Combining all scenarios together is more realistic but should be done after you have already learnt about the first tests. A combination makes it always hard to pinpoint "who is the problem"?
Don't forget to have someone manually test the system while you are running the automated performance test scripts. Learning how it feels if all of a sudden the performance goes down, is an invaluable information that numbers can hardly give you.
In a project I coached the performance test experts, it turned out the biggest amount of work was spent during the preparation of meaningful test data for the scripts. I mean, we were firing the tests on a real productive database, but finding accurate records with which one could perform the update scenarios without triggering this or that validation message wasn't easy. It turned out it was probably better if we created these data ourselves.
Not only this, we assigned each virtual users to work on only one particular set of data that others don't write to. If we didn't follow this approach, we had another challenge of locked records or trying to update something that was already updated beforehand that would have resulted in validation error messages. Next was the creation of records that allowed only one instance. A second record wasn't allowed. So we had to expand the script to also always delete right after the record was created. Also for this scenario, each virtual user had a particular set of cases that he/she could add new records to without getting in the way of another.
Friday, September 14, 2012
Everyday life at the Southern Hemisphere
Tuesday, September 4, 2012
Captcha #1
CAPTCHAs are used to prevent automated software from
performing actions which degrade the quality of service of a given
system and/or to protect the service from attackers trying to hack login credentials using brute-force attacks.Until now, I never had to test CAPTCHAs but thinking about it, testing CAPTCHAs automatically is impossible if testability isn't considered at all. Testability here could mean for the roboter to offer a backdoor which contains the correct clear-text. Of course such information should only be available to the script and de-activated when deployed live. Sometimes, even I struggle to identify the clear-text of the CAPTCHA, and I am NOT a roboter...
Thursday, August 30, 2012
The Thompson Test
I was impressed, because it took the doctor only seconds to make a clear statement without even asking me questions about where I feel any pain. Later, the magnetic resonance imaging procedure (MRI) confirmed the doctors' diagnosis. When I later googled the web, I learnt, the doctor executed the so called "Thompson Test".
Now, let's try to bring this experience into context with Software Testing. Of course, otherwise I wouldn’t have mentioned it in my blog. In contrary to the doctors, we testers usually look for bugs and not necessarily how to solve an existing problem. This is more typically the job of a software developer, although we testers also try to help as much as possible in finding some indication for the root cause of the problem (btw, works only if managers don't measure a tester's throughput by counting the number of bugs found...).
We use test techniques that are effective in one area and probably less effective in another. One such technique I use often for documenting software bugs, is the classification according to Kepner-Tregoe. By answering a set of simple questions you may either find the solution to the problem on your own (actually the main goal of this technique) or, if not, you provide at least some valuable set of information to the developer. This makes it much easier for him to localize the issue and become more efficient in solving it. If you want to learn more about Kepner-Tragoe, go ahead, GIYBF.
Additional we use logging tools (actually we have several ones), where we can grab the exact exception message; something that is typically NOT shown to a user because it might frighten him, but it is important for the testers and supporters to have access to, so the developer does not need to spend too much time investigating and trying to reproduce the issue.
TOJZ...still suffering the aftermath of my sporting injury for quite a while...
Thursday, July 19, 2012
How a double-click downed the backend-system
The cartoon was originally drawn 2012 by me and it has its roots in us testers suffering from the fact that sometimes our bug reports were not written well enough for the stakeholders to understand the importance of some bugs.
Just early this year (2019), I had an interesting experience for which this cartoon fits even better. This is the story:
When I say users, I mean internal developers and testers, because luckily we were still far away from going live. It turned out the system persisted a duplicate UUID. This duplicate piece of data caused the system to crash whenever a query was reading the affected record. I corrected the corrupt entry in the database and the problem was solved. But how the heck did my test suite manage to introduce such duplication? I tried over and over again but never ever did I manage to make my automated tests do the same thing again. As a consequence, the problem was considered low priority based on the assumption the probability for this scenario to re-occur was almost zero. In fact, over a long period of time, this never happend again, until slap bang - during a manual test - I double clicked the OK button in the web page to persist a new object. After a response time of about half a minute, I got the same system non-accessible message. Jackpot!
The cartoon fits perfect to another defect that we detected more than a year ago. A grey-scaled scanned document, when edited and rotated in program A, could no longer be viewed in program B, both tools that were used in parallel. But, the anomaly didn't gain enough attention as it looked like an edge-case and customers never experienced any issues until "slap bang" a customer could no longer export their documents because of edited, grey-scale documents. What followed was weeks of investigation and experiments/workarounds, all without a hunky-dory solution. So yes, that cartoon was like a precursor for the next ugly thing to happen.
ThanX to the The Testing Planet magazine editors who were so kind to publish my cartoon in their issue 8
Sunday, April 15, 2012
Good old times
Where I work, customers have no such choice. When we upgrade our releases, every customer worldwide either gets some new features or suffers from the fact that we have to deliver another series of extra releases to fix what we've broken in the previous update. Anyhow, it is only a question of time until cars also get equipped with software that you may or may not need to upgrade/patch on a regular basis in order to keep them running while all those oldies will still work fine without.
Friday, April 6, 2012
Automated Test Script Desease #1
And often, even if none of those typical UI test automation challenges is one that you face today, you will still have to sit there watching the script running, so you're ready for some extra test script babysitting actions. If you weren't there observing your scripts but going out for a coffee instead, don't expect your roboter to have completed successfully its job when you've come back to your desk...
That is just a few of the reasons, why I love testing below the UI so much.










































