Subversion problem with case insensitive filesystems

If you are using SVN with Linux/Mac and Windows XP you may run into this problem sooner or later. The cause of the problem is the case-sensitive characteristic of Linux/Mac systems not getting along with the insensitive Windows XP, which results in an error message like this:

 svn: In directory '.'  
 svn: Can't open file '.svn\tmp\text-base\qt_temp.N19845.svn-base': The system ca  
 nnot find the file specified.  

Fortunately the solution is quite simple, first access the working copy through Linux/Mac and remove from the repository the file that is causing the problem with the following command:

 svn delete --keep-local the_file  

Then commit your changes:

 svn ci  

Now go to your Windows XP system and everything should be working.

Joomla Basics: How to customize the style of a module

So you need to customize the look of a Joomla module? This is quite simple, just follow these steps:

1) Go to the backend -> Extensions -> Module Manager -> Find your module and set the name of the custom css that you will add

2) Refresh the page and check the source code. You will find the element using the new class name as shown below

3) Modify the css file and include the specific propreties you want for this module and use the name set previously

That's it, now you can make your modules look the way you want!

Removing MySQL from the Linux boot sequence

Do you want to speed up your boot time? maybe you are a software developer that doesn't require MySQL server to be up and running eveytime you turn on your laptop, and if you are running Kubuntu Lucid Lynx (10.4) like me, you probably already noticed that configuring the startup scripts via sysvrc conf doesn't work anymore.


You can read more about the change in this link, but the important thing right now is how to stop MySQL from loading next time you boot the computer:

• cd /etc/init directory
• sudo editor mysql.conf
  
• At the beginning of the file add a comment to the "start on" line (actually two lines)

In the same folder you will find other services that may be stop in a similar way.
 

Good deed of the day: can I replace my broken power adapter with a used one?

Most of you may be using a laptop to read this, and if you do you may already ran into the annoying issue of a broken power adapter. You don’t have to be an IT person to know that this is a critical part of your computer, but what many people out there don’t know is that you don’t have to get a brand new charger when this happens.

This post is aimed to all those people wondering “can I use a different brand or model charger to replace mine?” the answer is: yes, you can and you should!

Why you should? Well it is very common to hear from people that they want to help and do something good for the world but they either don’t have the time or the energy to join an NGO or a project that works in the area, but it is in our everyday decisions where we make the biggest impact on the world and reusing and old adapter instead of buying a new one is a perfect example of how you can contribute to having a better and more sustainable society.

Now just keep in mind the following rules before doing your good deed of the day:

• -Check the adapter jack and make sure that they are almost the same diameter and length to make sure that there is a good connection.
•  
• -Check the label on your adapter and find the voltage and amperage.
•  
• -The voltage can’t be too different from the original one, e.g. I just replaced a 19.5V adapter with a 19V one without any problems.
•  
• -The amperage has to be the same or higher than the original one, e.g. replacing a 3.34A for a 4.70A won’t hurt.

Drawbacks of this? Some adapters won’t recharge your battery if they are not from the same brand and model as the original one, but it is very likely that by the time your adapter breaks your laptop has been already been used for a couple of years and the battery is useless anyway.

Just for the records, I replaced a Dell Inspiron 1501 adapter with an Acer adapter (model AP12AD02) and it works perfectly.

Spanish version of Facebook got hacked

Did Facebook all of the sudden got very impolite? mmmm nope, it seems that the Spanish version of the social network giant was hacked and (at least for some profiles) now instead of wishing you happy birthday it says... well check the image below

Well another day, another hacked site...

JVM Heap Size Tuning

Earlier this week I had to solve a major performance issue affecting our application, in the end it turned out to be a database (missing statistics) problem that lead to a slow response from a query, but in the mean time I had the opportunity to play a little bit more with Websphere’s JVM Heap size settings.

First of all, what is the JVM Heap size? The simple answer is: The amount of memory used by the virtual machine to allocate new objects created by your Java applications.

You can find tons of details about it online, but here I’ll post the main ones:

·It directly affects performance, so it’s one of the most important JVM tuning parameters

·If you set the max heap size too low, your apps will reach the max level soon and you’ll get the following error:

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space

·In case you choose big amount for the max heap size setting, then your applications will have all the room needed to create objects, but then the Garbage Collection (GC) process will take longer. The effect of this setting will depend on the GC policy you choose.

By default the GC policy is set to “Optthruput” which means your app will not respond during GC. The second option is “Optavgpause”, that runs the GC concurrently with the app and gives a better response time. Finally “Gencon”, that treats long-lived and short-lived objects in a different way by allocating the latter ones in a special area (Nursery space) that can be disposed more often, hence reducing the time spent during GC.

In the end the value of the heap size will depend on the needs and resources available in each case, so now it’s time for you to go and give it a try ;)

The Inner History of Devices

An interesting presentation by the famous MIT sociologist Sherry Turkle called "The Inner History of Devices". In the 30 minutes of her presentation (followed by 30 minutes of Q&A) the talk brings you back to a hidden subject within our daily lives: the feelings we have for our devices.





Check it out and you'll come up with your own ideas about the subject, in my case it made me realize that my wife's idea of me having an emotional attachment to my laptop actually makes sense! Think about it, I work, talk to my family, connect with old friends and have fun through the same device, so who could blame me?

Now take a couple of minutes, and think about the device that has or is affecting you the most ;)