Interesting times
May. 5th, 2009 07:24 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
liam_on_linuxBeen playing with Ubuntu 9.04 on my Thinkpad X31 since a month or so ago. Mostly it runs rather well and the onscreen notifications look great.
The snag is that since Compiz display compositing started working in 8.10, it's been dog-slow on this machine. The wobbly windows were nice, but utterly useless and ssslllooowww, so I turned visual effects off.
Snag is, this doesn't disable Compiz. It merely turns the SFX dial down to 0. X.11 is still painfully slow - Gmail couldn't keep up with my 4-finger typing and window scrolling - even in a GNOME terminal - was a case of 1 screen update per second. And this on a 1.6GHz Pentium M with a gig of RAM and a 7200rpm 150GB hard disk: not state-of-the-art, but not a slow PC and faster than any Atom-powered "netbook".
To go to a 2D window manager, you need to switch to Metacity manually, either from a terminal:
metacity --replace
Or by installing and running the fusion-icon panel applet and selecting Metacity from the menu.
This works, but the speedup was only modest, and typing and scrolling weren't much improved. So Compiz itself is not solely to blame - and thus uninstalling it would not help!
This being the case, then it must be the AIGLX indirect-rendering X server that's doing it.
A hint from the Ubuntu mailing lists suggested adding a line to /etc/X11/xorg.conf:
in the "Device" section, add the following line:
Option "DRI" "off"
I tried this, and the speedup was dramatic. Web pages scroll like lightning and a terminal can zip through the output of dmesg in a second or so.
My only mistake was then trying to re-enable Compiz, just to see what happened. What I got was a blank white screen. Hitting Alt-tab showed corrupted versions of the various open app icons, and a shadowy outline enclosing nothing. A reboot showed that the wallpaper was displayed, but nothing else.
I disabled it again and all is well.
I'm a bit unimpressed, though. For one thing, this option shouldn't be on by default if it's unusably slow on certain chipsets. Methings this is an option for machines with fully-hardware-accelerated OpenGL only. Secondly, that Compiz appears not to check to see whether the X server supports the features it needs as it launches, meaning an unusable system if DRI is not working, rather than a graceful fallback.
Ubuntu 9.04 is pretty good - it's polished, it boots much faster than before, it looks great, the new notifications are smooth (although they probably ought to have used the existing Mumbles rather than creating Ayatana Notify-osd from scratch) and it's all very neat.
But there are still some very rough edges below the surface if you scratch in just the right place...
The snag is that since Compiz display compositing started working in 8.10, it's been dog-slow on this machine. The wobbly windows were nice, but utterly useless and ssslllooowww, so I turned visual effects off.
Snag is, this doesn't disable Compiz. It merely turns the SFX dial down to 0. X.11 is still painfully slow - Gmail couldn't keep up with my 4-finger typing and window scrolling - even in a GNOME terminal - was a case of 1 screen update per second. And this on a 1.6GHz Pentium M with a gig of RAM and a 7200rpm 150GB hard disk: not state-of-the-art, but not a slow PC and faster than any Atom-powered "netbook".
To go to a 2D window manager, you need to switch to Metacity manually, either from a terminal:
metacity --replace
Or by installing and running the fusion-icon panel applet and selecting Metacity from the menu.
This works, but the speedup was only modest, and typing and scrolling weren't much improved. So Compiz itself is not solely to blame - and thus uninstalling it would not help!
This being the case, then it must be the AIGLX indirect-rendering X server that's doing it.
A hint from the Ubuntu mailing lists suggested adding a line to /etc/X11/xorg.conf:
in the "Device" section, add the following line:
Option "DRI" "off"
I tried this, and the speedup was dramatic. Web pages scroll like lightning and a terminal can zip through the output of dmesg in a second or so.
My only mistake was then trying to re-enable Compiz, just to see what happened. What I got was a blank white screen. Hitting Alt-tab showed corrupted versions of the various open app icons, and a shadowy outline enclosing nothing. A reboot showed that the wallpaper was displayed, but nothing else.
I disabled it again and all is well.
I'm a bit unimpressed, though. For one thing, this option shouldn't be on by default if it's unusably slow on certain chipsets. Methings this is an option for machines with fully-hardware-accelerated OpenGL only. Secondly, that Compiz appears not to check to see whether the X server supports the features it needs as it launches, meaning an unusable system if DRI is not working, rather than a graceful fallback.
Ubuntu 9.04 is pretty good - it's polished, it boots much faster than before, it looks great, the new notifications are smooth (although they probably ought to have used the existing Mumbles rather than creating Ayatana Notify-osd from scratch) and it's all very neat.
But there are still some very rough edges below the surface if you scratch in just the right place...
