Archive for February, 2008|Monthly archive page
Disclaimer:- I am kernel developer and I use Ubuntu a lot, at home, at work , on my central repository and backup server.
This is not a rant, but a genuine flaw i have found in the Ubuntu’s armour.
The meteoric rise with Ubuntu is phenomenal, it is good for FOSS community, for people because it gives them a choice, for average joe user because it works without much fuss(mostly).
All is cool, ubuntu works great(tm), no problems.
Ubuntu seem to have got everything right for average users.
But it lacks when it comes to users who do not fall into the category of being average.Don’t get me wrong, I am not whining for stability issues at desktop. I am talking about people who use/want to use Ubuntu on servers or as a development environment. Assuming that Ubuntu follows Debain’s legacy of stability seems to be a misnomer at some places.
These places, are dark sides where very few lurk into.I am one of those and i found Ubuntu not up to the mark.
Ubuntu’s builds turn out of be buggy and these includes a lot of packages which would be deployed on a server.
Has ubuntu ignored that Linux(including Kernel and userspace tools) itself is a pretty stable?
I see this as a smaller part of the bigger picture.Ubuntu does not have privilige of company of same hackers RedHat or Suse has.Well this does not means that RedHat and Suse builds are bugfree.
I am no fan of AMD, VIA or any other processor manufacturer. I use AMD at home and Intel at work. And in my experience AMD’s processors may have lost to reborn netburst architecture based Intel processors, they still are technically good for *me*.Why?
Here is the rant. Intel makes some really shitty processors as far as virtualisation is concerned(read VT technology in Intel lingo). Intel’s architecture allows only protected mode instructions to be virtualized and not the real mode instructions. This may sound like – “Okay, who cares about real mode instructions anymore? We all are using 32/64 bit protected instructions these days”. Thats right, but thanks to IBM and brethren we still have to rely on real mode instructions while booting initially. Many bootloaders which use some real mode instructions will not be able to do anything under guest virtual machines booting under a VMM.(e.g while installing a HVM Guest under XEN) The intial part of the setup to switch to a protected mode is done with the help of some real mode instructions and thus cannot complete resulting is a blank screen or an endless wait. Example :- You cannot install a guest from a standard Linux ISO, if the loader on ISO uses real mode instructions(BTW isolinux does use some AFAIR).
Fret not, there is a solution. Emulate, yes emulate every real mode instruction rather than virtualize under intel architecture. Sounds like suckage, yes it does. So somethings may work and some may not depending on whether the instruction has been emulated or not.
FWIW, AMD has a better and clear virtualization capability, all instructions can be virtualized irrespective of the real/protected/legacy mode.