Miscellaneous Knowledge

I recently got mobile broadband from Voadafone UK (3GB/mo for £15/mo). Now, while they advertise “upto” 7.2mbit/sec, I appreciate that you will never recieve it - the same with Wireless Networks, you never receive 54mbit/sec, even right by the WiFi point you will probably get just 30mbit/sec at most.

Anyway, you should expect to get around 2mbit/sec from your mobile broadband if your modem for it supports 3.6mbit rate or higher. However, I have heard complaints from some that they are getting extremely slow internet.

If your Mobile Broadband Access Program (e.g Vodafone Mobile Connect) is showing GPRS connection, then you are on the 2G standard of mobile internet access, giving you a speed similar to that of a dial up modem. GPRS is the “fallback connection”, when there is not enough signal for a relibable 3G or better connection.

Therefore, to get a faster speed, you need to get a better signal. The best way to do this is to relocate your modem. Many MBB modems now are based off USB, so you can buy an inexpensive USB Extension cable to move your modem to a better location. If indoors, try moving the modem to a windowsil. Do not put it outside at all, no matter what you wrap it in!

You can also look (in the UK) at SiteFinder, the UK’s database of Mobile Phone towers. You can then see where your local tower is and position the modem best.

Hopefully these steps will help you to get a faster speed - enjoy!

One thing i’ve come across while hosting games is the number of people that don’t know how to use FTP, or use a very bad method (i.e web based 3rd party FTP sites). So, i’m going to show you how to use FTP properly.

This tutorial is aimed at Windows users, those that use other operating systems will probably be able to follow these instructions with a bit of alteration.

First thing is to select your FTP client, which enables you to connect to the FTP server. While most operating systems have one, it’s quite lacking - it works but you’re going to have fun getting it to do that. Therefore, I recommend FileZilla, a free FTP client that works on most operating systems (Windows / Mac / Linux). I use FileZilla and hence it’s going to be the basis of this tutorial. Download it here. I’m going to assume you know how to use an installer.

Once installed, simply run FileZilla. On Windows, you will find it in Start > All Programs > FileZilla FTP Client > FileZilla. You should then be presented with the following screen;

Lets go over the basic functionality of this screen. The boxes at the top that read “Host”, “Username”, “Password” and “Port” are where you enter the details of the FTP server you want to connect to, then click QuickConnect to connect to it.

The currently empty box under this will show you the status of the FTP, the messages it shows might not be understandable by you, but if you’re having problems with your FTP, the host will need to see this to help with your problem.

The box on the left shows your local files, on your computer. When connected, the box on the right will show the contents of the remote server.

Finally, the box at the bottom will show you the progress of your transfers, if you have any.

So, enter in the FTP information that your host gave you and click quickconnect. You can leave the port box blank unless your host has told you to use a port other than 21.

So, you’ve now connected, the box on the right is now filled with the contents of the remote server, if you’ve just got FTP access there might not be anything there - hence you have to upload files. The screenshot above shows me connecting to the FTP site for this blog, hence all the blog files are seen on the right side.

Now, I want to upload a picture, so I simply browse to the location of the picture on my computer on the left and drag the file I want to transfer over to the remote site on the right. Now at the bottom you can see that there is a progress bar showing how the transfer is going, along with an estimated time. If you transfer multiple files, then you will see multiple file transfers reported.

It is that simple, and the process can work in reverse too, you can copy files from remote to local. FileZilla has many other features too, such as detecting when a local file is changed and prompts you to upload it. No matter what your needs, FileZilla can probably fufill them, plus it’s free!

I highly recommend FileZilla over any other solution, while others might have better features such as Synchronisation, they are not exactly free. If you’re currently using your operating system’s inbuilt FTP or another client which isn’t working for you, get FileZilla now.

Customers of my Game Server Company may have noticed recently that we moved to a new server (if you didn’t notice, you probably didn’t get the several emails I sent out informing you of progress every step of the way!). Anyway, I noticed today that between them, CSRSS.exe and Hardware Interrupts where taking up 25% of the total processing power, which is exactly one core (it’s a quad core server and since CSRSS isn’t multi core aware it can only max out 1 core).

Normally, CSRSS uses less than 1% of total CPU, and Hardware Interrupts only uses a lot of CPU if there is a problem (such as your disk drive being put into PIO mode). I adjusted the affinity of CSRSS so that it only used one core, and all of the hardware interrupts also happened then on that core. CSRSS was defiantly at fault here.

A quick bit of Googling lead me to MS KB 934330. This describes an instance where CSRSS uses more than 50% of CPU resources when connected via remote desktop, which is the problem I was experiencing (i’m assuming they are using just the 1 core). While there is no official patch, they have a hotfix available, and recently Microsoft have started being a bit more generous with Hotfixes, you don’t have to contact support any more - just get it sent straight to your email.

I applied the hotfix, rebooted and the problem had gone away - no more CSRSS using lots of CPU. If you also have this problem i’d reccomend applying the hotfix rather than let CSRSS waste your CPU cycles.

Oh, if you’re wondering how I viewed Hardware Interrupt CPU usage, I use Process Explorer - an excellent replacement for task manager, showing CPU to 2 decimal places, and lots of other handy features. Plus it’s regularly updated and free.

If you’ve ever set up MediaWiki, you will probably know how difficult it is to get equations (or LaTeX rendering / math tags) working. Under windows, it requires a lot of tweaking, ImageMagick support, a full LaTeX install and in quite a few cases fails to work. While trying to get equation rendering working on my personal (read, private!) wiki, I came across an interesting solution to this problem. Simply put, it is in extension which interprets <tex> tags and then sets the image URL to that of an image generated by a CGI-Script on another page. This means that no LaTeX or ImageMagick support is needed on the localhost.

The full details of how to get this working are documented here. It is very simple to set up, with the only drawback being that you have to use <tex> tags instead of <math> tags.

If you are interested in the script itself, perhaps to use it for something other than a Wiki, you can visit the creator’s site here. If you have a large wiki or other project however, it is recommended that you host the CGI script yourself to reduce the load on the server that provides this free LaTeX equation rendering.