threading.Thread vs. multiprocessing.Process
The Feather or the Anvil? 
First a bit of background: I was tasked with created a high level tester for my company’s system. The idea is create 1 or more monkeys to pound away at the company’s product for a very long time. A concurrent parallel programming project with the requirement that it needed to be compatible with 2.6.2 version of Python.
With threading, you get real posix threads (pthread) which works pretty well. They implicitly share state with the parent thread and do not use IPC or messaging. They have low latency and low overall resource footprint.
However there are drawbacks that made further development using threads a real problem. that is the use of signals. Such as threads not handling signals, working with the global interpreter lock (GIL, only one thread allowed to run at a time), and more. Read more
xorg 1.9 versus fglrx
With the release of Ubuntu (Meerkat) 10.10 just 10 days away, the ubuntu x-swat people have been busy getting fglrx ready for release. The fglrx now compiles against latest Meerkat kernel and finally resolves the unknown symbol issue.
In the laptop is a ATI Mobility Radeon HD 3670 and with the latest fglrx driver usability is awful. There is horrible tearing when using “Appearance -> Visual Effects -> Normal”, which had to be set back to “None” just to be usable. Even on “None”, scrolling down in documents, chrome, firefox and Skype all give blurred or stuttered graphics.
These are for me “do not use” releases.
Read more
Ubuntu 10.10 Maverick Meerkat on Dell Studio XPS 1640
After a brief time with Karmic (10.04), the laptop was upgraded to the beta of Maverick. Everything works out of the box with no additional tricks necessary in getting the Dell Studio XPS 1640 fully functional.
The only drawback I found in upgrading from Karmic was the loss of fglrx as a xorg-server driver. Maverick is shipping with the 1.9 version of xorg-server which is ABI incompatible with what fglrx is compiled against.
The exact error is:
undefined symbol: savedScreenInfo
which causes X not to start.
The rumour is that ATI will release a fglrx package that is compiled against 1.9 version of xorg-server when Maverick ships on Sunday, October 10th. Read more
xdd is not “extreme dd”
While the ladies and gentlemen at IO Performance Inc. are busy with their 7.0 “Phoenix” release, they have left their website in disrepair including the disappearance of their product, source code and documentation.
Since I make heavy use of xdd and apparently I am not the only one that needed the documentation, source and binary; I have provided it here for everyone.
xdd65.013007.tar
xdd6.5 documentation
Read more
Make your external screen your primary screen
Or how to move gnome panels to a different monitor in Ubuntu.
In my particular setup, I have a laptop and a much larger external display. I like having my main Gnome panel on the external display and use the laptop display for other things like Skype and email.
To make this change perminant, I use some gConf magic: Read more
