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Hamachi Bug – DNS problem in windows

I have installed hamachi on my windows 7. When I change my network adapter, after a while my computer cannot resolve DNS addresses. For example, at home I use WiFi. I suspend my computer and go to the office. At work I connect to the wired Ethernet connection (i.e. change the network adapter) and after a while my system is unable to resolve DNS addresses.

Solution for this is either to reboot the computer or disable the hamachi adapter from Network Connections (Control Panel\Network and Internet\Network Connections).
 

Convert (Export) Excel Chart to EPS Using Adobe Postscript

You may need to export a nice chart from Excel to EPS so that you include it in your Latex project. Here is one way how you do it.

1. You need to install Adobe Universal PostScript Windows Driver Installer 1.0.6 (or newer). If you have Vista or Windows 7 or some newer version run the installer with compatibility for Windows XP SP3.

– To set the compatibility for the installer, right click the file and select "Properties". Then from the "Compatibility " tab select "Run this program in compatibility mode for:" and select "Windows XP (Service Pack 3)"

 Select Compatability Mode

2. Open your Excel File.

3. Select your chart.

4. Select from the (File) menu print

5. Select the Adobe printer in my case this is "Generic PostScript Printer"

6. Ensure that "Select Chart" is the selected option in "Print what" area. If you did not selected the chart then this will option will not be selected. Go to Step 3.

7. Select print to file check box.

8. Go to Properties

Print Dialogue Box

9. In the properties dialog window select "Layout" tab then press "Advanced" button

10. In the Advanced properties dialog window, under the node "Postcript options:" select "Encapsulated Postscript (EPS)"

11. In the printer dialogue window, when you press "Print" you will be asked for the file name to be saved. You are not asked ensure that you have selected "Print to file" Step 7. Write the path and the file name something like "c:\chart.ps". If you don't include the full path I don't know where the file will be saved by default.

12. Use ps2eps to convert the saved PS format file into EPS format.

Profiling with VTune

I have just seen one tutorial about using VTune to profile an application. The tutorial covers the different aspects that should be analyzed to understand the performance of the application – including cache misses, thread parallelisim, cache line sharing, cycles per instructions (CPI). The tutorial is available at "Using Intel® VTune™ Performance Analyzer Events/ Ratios & Optimizing Applications".

Using DropBox in Eee PC with Xandros and KDE

DropBox is very convenient online back-up and synchronization service. It has a free version with storage capacity of 2GB.I started using it recently and liked it pretty much. I have the client application installed in one Windows, one Ubuntu and now Eee PC Xandros machines. Using it on Eee PC Xandros was a little bit tricky. DropBox consists of two components daemon and Nautilus plugin. The functionality of the serivce is in the daemon that runs at the background and monitors for changes in the Dropbox directory. The Nautilus plugin is a convenient front-end to the DropBox daemon that provides interactive GUI. The problem of using DropBox in Eee PC Xandros and in general KDE is that Nautilus which is a Genome application. And to install the available binary packages you need to install all the required Nautilus/Genome dependencies (packages). I don’t recommend trying to install these dependent packages because this may lead to uninstalling existing packages thus creating critical dependencies that may cause your system to not run at all.

So how I use DropBox in Eee PC with Xandros. I install only the daemon and don’t have the fancy file annotations and other features that comes with the Nautilus file manager:

  • Download the binary of the DropBox daemon from http://www.getdropbox.com/download?plat=lnx.x86 (this is 32bit version of the binary but should work also on 64bit architectures)
  • Then unpack the tar file ($tar -xzvf <file name>) a hidden directory with name .dropbox-dist will be created
  • move this directory to your home directory ($mv .dropbox-dist $HOME) 
  • now you have to run the DropBox daemon – this is the executable named dropboxd inside .dropbox-dist ($ ~/.dropbox-dist/dropboxd). A login dialog box will appear. Type in your credentials. The default DropBox directory is /home/user/Dropbox. If you get errors you have to upgrade some packages. Better apply all possible upgrades otherwise you can get broken packages (from CTRL+ALT+T, sudo synaptic, choolse "Mark all upgrades", Apply)
  • DropBox daemon will start synchronizing your files (downloading your files from the web storage)
  • The DropBox daemon will run in background and take care of keeping your directory in sync.

However these steps are not sufficient to make DropBox run automatically every time when you boot your computer. To make DropBox daemon run at startup you have to add the following line

/home/user/.dropbox-dist/dropboxd &

Any comments on improving this post are welcome.

 

Eee PC 901 – Thinking of Switching to Ubuntu (Easy Peasy)? Don’t!

I use Ubunut in my other more powerful laptop and I am very satisfied with it. After the clean install, I configured it very well and now it runs perfectly. So I decided to try Ubuntu Easy Peasy (I think the version was 8.04.1) on Eee PC 901. I had reinstalled Xandros in my Eee 901 which worked very well, I didn’t have any complaint’s but with installing some packages (dependencies). However installing Ubuntu Easy Peasy was completely waste of time.

Things that didn’t work out of the box are:

  • Webcam
  • Bluetooth (I am not able to connect with my mobile phone to the Internet)
  • Wireless with WPA encrypted networks
  • Function key (Fn)
  • Microphone
  • The video files (movies).

Though there are known solutions to make all these working I didn’t want to waste my time with and restored back the Xandros which I had backed up.

And one more thing that I was not satisfied with is the noticeably slow boot time of Ubuntu Easy Peasy compared to Xandros Easy Mode.

For other Eee PC models probably these probably do not exist. If you want to try Ubuntu on your Eee PC there is very nice how to article “How to install Easy Peasy (formerly Ubuntu-EEE) on an EEE PC”. But in case that you may also not like it, I would recommend you first to back up your system.

Windows XP – Microphone not Working

Today I had to fix an annoying microphone problem on my brother’s computer. He has Windows XP Professional installed and the microphone was not working – unable to use the microphone in any application. The solution to this problem is very subtle since you have to enable "MIC boost" a very hidden feature. Here is how to do it:

Open the extended Version of Volume Control (down right next to the clock, right click and select properties).

You have to see the following picture:

In Volume Control dialog:

  1. Ensure that Muted is checked for microphone (if not you will be able to hear yourself on the speakers when talking to the microphone)
  2. Then click Advanced for Microphone and select "MIC boost"

Then Close everything and now your microphone should work properly.

Sorry that the first image is in Bulgarian. I will change it as soon as possible.

Is Linux Easy to Use?

This morning while we were drinking coffee with my home mate Cristian, we had a small discussion if Linux is easy to use? I and my friends have many times been talking about that and this time the topic opened again because yesterday I bought a new Eee PC 901 Linux laptop and its wireless didn’t work out of the box. Our conclusion at the end of the coffee was that Linux made great step ahead. Today it is very user friendly, intuitive and easy to use – particularly the Ubuntu distribution, than it was before 10 years. But it is not as friendly as Windows or Mac OS are. Because this article may make many enthusiastic Linux users angry, I would like to say in advance that it is not “Linux is bad and other operating systems are good” kind of writing, at all.

I use Linux for long time probably 10+ years. It is very powerful, reliable and stable operating system (this does not imply that the other OSs are not). But I think that it is difficult to use by people with little knowledge about computers such as my brother and mother are for example. Sooner or later, a Linux user will need to edit some configuration file, or script, do something on the terminal or even probably compile some library, module or application. There isn’t anything wrong with that if the user is computer science student for example. But this horrifies the common user – the common user does want everything to be intuitive, automatic and with minimal options.

I think that the difficulty of using Linux is not in the GUI but the configuration and setup of the system. I find the GUI (KDE and Genome) is rich and intuitive enough. But the problem is for example when you just install the system and some driver is missing or bought a new non-standard hardware. Then you can spend days to make it running.

What are the Current Problems?

I identify three points that make Linux difficult to use or less preferable (not ordered by importance):

  1. Unsupported device drivers
  2. Software management and library dependencies
  3. Not sufficient commercial quality software

Unsupported Device Drivers

Many hardware companies do not develop Linux drivers for their devices. What happens is let’s say a volunteer developer tries to implement these drivers manually by revers engineering those available for other operating systems. These drivers then cause the device to not function properly and frustrate the end user because of poor experience. This problem was much more evident before but today when most of the interfaces are standard is less important, but it still exists. For example, it took me few days to make my web cam running in Linux, or the microphone working with the messaging applications (these are not relevant to the EEE PC, there everything worked out of the box). A common user wouldn’t cope up with these problems as it required me to search on the web, write on forums and read posts, compile kernel modules and modify scripts to load these modules at start up. In the earlier distributions of Kubuntu I had a problem with suspend and resume – a small but frustrating problem.

Software Management and Library Dependencies

Linux is open source and the complete system (not just the kernel) comprises of thousands of open source libraries and programs. Open source is something great – it is not just sharing but a philosophy. Everybody can develop an application or a library. Then somebody else takes it, and implements a program which extends the features of the previous library or builds on top of it. But this creates the problem of the dependency – my program depends on the interface of a specific version of a certain library. So if you want to install my program you have to find the exact version of the library that my application depends on. But what if another program depends on a different version of the same library. We have a conflict. Of course, the example I gave here is idealized and much simplified than it is in reality. This problem was very serious before. The Advanced Packaging Tool  (APT) first introduced with Debian (it might be possible that apt tool originates from other distro that I don’t know) brought a light to this mess. But again the problems exist but this time termed as broken package. For example, when I installed my Kubuntu 8.10 Intrepid my standard wireless didn’t work with the WPA encrypted network. The problem was in the knetworkmanager. It took me a week to fix it because I was one of the first experiencing the problem and yet there wasn’t an existing solution. Other problem I have is playing back the video files – a problem caused due to a bug in the XVideo and beryl/compiz better described at "Video playback problems (black) after installing Beryl (or Compiz)" (ok this is not much relevant with broken package).

Not Sufficient Commercial Quality Software

I think that there is much less commercial quality software targeted for general home or office end users for Linux than for Windows or Mac. Let me clarify my classification of "software targeted for general home or office end users" by giving example applications that fall in this category:

  • Multimedia editing and organization – particularly video editing.
  • Games.
  • Office – I find Open Office to be pretty good for home use but not office where time costs money.
  • Image editing – Gimp is powerful but hunting for plug-ins and installing plug-ins is not for general users.
  • And other that I cannot recall but would add later.

However there is very good commercial quality open source special purpose or domain specific software for Linux. Examples are gcc, Firefox, Emacs, Apache, I do think Open Office and Gimp are good, may libraries such as glibc and STL and many other that I cannot list here.

What Improved in Linux?

We also talked about what improved in Linux for the past 10 years let’s say:

  • Easy installation.
  • More intuitive and rich GUI.
  • More software for home and office use was developed.
  • More supported device drivers.

Easy Installation

Today’s Linux distributions such as Ubuntu, Suse and Fedora can be installed very easily. In Ubuntu the user required actions are just 4-5 clicks. The installer is clever enough to partition the hard disc without loss of data and co-living with other operating systems installed prior. I love this feature a lot.

More Intuitive and Rich GUI

KDE4/Genome combined with a compositing window manager such as compiz/beryl make the user experience exceptional. These fancy desktops are what the end users want – including me :).

More Home and Office Software

  • Codecs and applications for playing video appeared such as kaffeine, Mplayer, and Totem, xmms appeared.
  • Applications for organizing photos such as Picasa and digiKam.
  • Word processing – Open Office.
  • Internet – Firefox, Thunderbird, Evolution.
  • Games – I am not a game fan and don’t know which popular games are available on Linux but I heard this from my friends.

All these improvements made Linux attractive for home and office end users. That’s why some computer manufacturers considered to ship some of their PCs with preinstalled Linux distribution thus decreasing the market price of the product. Once you have your Linux distribution configured, setup and running one can be happy with it. So refining my answer of the question "Is Linux easy to use?" would be more correct to say "It is easy to use Linux, but difficult to configure and set it up.". And now another question may arise – "Where is the boundary of using and configuring?".

References

Here are some references relevant to this article.

 

Better small fonts in Ubuntu 8.10 (intrepid)

After an out of the box install of Kubuntu 8.10 Intrepid all my fonts seemed to me too large. These large fonts don’t seem very elegant and thankfully I also don’t have vision problems with my eyes. The article "The Absurdity of GNOME Font Sizes" discusses about the big fonts in ubuntu but does not tell much how to make our fonts smaller. So I decided to look around the settings what do we have and after checking my appearance settings I could set nice looking smaller fonts globally on my desktop.I achieved this nice effect from

"System settings->Appearance->Fonts".

Here you have to:

  1. Enable "anti-aliasing" or also font smoothing. This makes your fonts more smooth – less edged – and the text is more easy to read.
  2. From the extra configuration options for anti-aliasing disable "exclude range" and enable "use sub-pixel rendering". In the first option the default range is small and will not affect the small fonts – the result will be that letters will look edged. Sub-pixel rendering enhances the quality. Current computers are powerful enough so that these changes will not make any visible performance impact.
  3. Now you have to also choose: "Force fonts DPI" to be 96 DPI. Actually this is what makes your fonts look smaller. I use 1400×1050 so this DPI for me looks pretty OK. If you have lower resolution and want smaller fonts probably you may either think of encreasing your desktop resolution or tweeak the fonts size DPI manually to some lower value of 96DPI. The article "How to change the X11 DPI under kUbuntu" tells more about custom DPI settings.
  4. Then you have to logoff and login so that chages take effect.

I wished I put some screen shots to demonstrate the effect but I am lazy now to revert back and forth with my configuration. Probably later.

 

Problems with IBM Lenovo T60 Laptops

Since August 2006 I use IBM Lenovo T60 laptop. It is very stylish laptop. I have it dual boot Windows (had XP and now have Vista) and Linux (Ubuntu). It works perfectly with these operating systems. It is very easy to find drivers. I love the high resolution 1400×1050 on 14" screen and the overall performance delivered by 1.8GHz Dual Core and 4G Ram.

BUT

Since August 2006, because of technical problems I changed 2 laptops and this is my 3d one. Also my colleagues experienced similar problems and in our team 5 out of 12 member have changed their laptops at least once because of various problems – mainly cooling fan failure. In my particular case the problems were as follows:

  1. The battery of the laptop was taken off and my home mate accidentally unplugged the power cable. After that the computer didn’t turn on. I had to change it.
  2. The computer start overheating and rebooting. This damaged my file system and I spent 2 days trying to restore my lost files. The problem was problem with the fan.

Other main problem of these computers is the battery. We have 6 cell Li-On batteries. Their life is extremely short. I changed my first battery before about 3,5 months and it was completely death. I got my second battery provisional. When I got the second battery IBM’s Power Manager software was showing:

  • First used date: September 2006
  • Condition: Good
  • Store Capacity: 88%
  • Cycle count: 78
  • I was able to use the computer for 1,5-2 hours

Now after using the for 3,5 months the Power Manager software shows:

  • First used date: September 2006
  • Condition: Poor
  • Store Capacity: 44%
  • Cycle count: 110
  • I am able to use the computer for 30-45 minutes

So for 3,5 months the performance of the battery life dropped to more than two times. I am not battery expert but this is very bad performance for a battery. One of my colleagues also changed his battery and other is about to change so 30% of the people in the team. Unfortunately this post became a bit criticising but after seeing the notification for changing my battery because of its poor performance I decided to write about the negative sides of my personal experience using IBM Lenovo T60 laptop.