Archive for February, 2010

I have to admit, I’m a huge fan of Movies and TV shows that have some fiction involved. Movies like “Avatar” and TV shows like “Heroes”, “Lost”, and “Flash Forward” are my favorites.

Nowadays we have come a long way to making the screen look real. Remember the first Star Wars movie (and how mind blowing it was) and looking at Avatar now (and how mind blowing it is!). Worlds apart.

If you ever wondered how it is done and are into Visual Effect’s I recommend that you check out the StarGate Studios YouTube Channel. Very good stuff. One of my favorites is below.

IMG_0164.PNG The last couple of weeks, I have had to use the Internet Tethering function that comes with the iPhone. During the course of this time, I made some interesting experiences that I would like to share.

Phone Calls
There is one thing I learned the hard way when I enabled Internet Tethering and wished that someone would have told me. That is, that when you don’t have a 3G coverage, like only Edge (the “E” in the upper left corner as shown in the images on the right), you will NOT be able to receive any phone calls during Internet Tethering.

Thus if you need a Internet Connection and you want to be able to receive calls make sure that you are on a 3G network.

Battery
We all know that the iPhone has miserable batterie life. When you enable Internet Tethering you have two options how you want to connect to the iPhone. One is over Bluetooth and one is with the USB cable.

For keeping your iPhone “alive”, I recommend that you connect it over the USB cable. Thus you will not drain your iPhone batterie extensively and will charge your iPhone at the same time. but there are two important things to know about this method:

1. While your iPhone is connected over the USB cable and charging it will also suck the batterie from your MacBook extensively. So, make sure that you connect your MacBook to the power outlet when you have your iPhone hooked up per USB.

2. Contrary to the above I have noticed that the iPhone is NOT being charged, even thought connected over USB. The reason for this is that as more connection you have open over the Carrier network the less the Mac is able to charge the iPhone. It is like the connection (of the USB cable) is fighting with the power, since both go over the same cable. The remedy is to lower your usage for the connection, like closing your eMail application or lowering how many times you get your eMails.

Other things…
Some of the things that I wished would be really different from a user perspective are;

… Every time I have to make a call, Internet Tethering is automatically turned off! Meaning I have to reenable it manually after the call is done. That means, clicking on “System Preferences”, then on “General”, then on “Network”, then on “Internet Tethering”, then enable it and selecting “USB”. That makes it 5 steps, 5 steps too much!

… The iPhone does not switch from Edge to 3G automatically. The only remedy I have found to this is to enable Airplane mode and the disable it again. Right after, the iPhone selects the nearby 3G network (until the next time it is back to Edge).

Nginx is our favorite web server currently as it is fast, lean and easy to configure. Performance is just outstanding and if you haven’t take a look at it.

One thing that I noticed while we deployed Nginx with Tomcat is that their default size for the buffers are very low. Don’t know why a 4K buffer size would be sufficient. If you keep it at their default size and might have a heavy duty Tomcat app then it could be that you will see error messages like:

upstream sent too big header while reading response header from upstream

The remedy for this error is to set the parameters for higher values for the proxy_buffer* parameters as we have done and now all is back to normal. Here are the current settings that worked well for us;

proxy_buffer_size   128k;
proxy_buffers   4 256k;
proxy_busy_buffers_size   256k;