[plug] making linux desktops consistent

[Craig Ringer]

On Tue, 2004-04-27 at 23:55, Shayne O'Neill wrote:

> The X terminal stuff worked well, but theres a world of diference between
> running a KDE desktop and a fluxbox desktop, and this is where the plan
> kinda falls apart. Fluxbox while perfectly mofo for you or I is plain
> baffling for joe shmoozer.

Huh? I use KDE over remote X from a P133 with 32MB of RAM at work - it's
quite reasonable to use. I have as many as 12 users at once, though
admittedly only a couple are presently using KDE. When connected over
10/100 e/net from my P/900 laptop I hardly notice the difference between
that and working locally on the server.

> I found two "duck terminals" (yeah, we got some bizare tech humor round
> there) is about the limit before it starts really slowing down. The app
> server is a intel 1.6gz with 256m mem. Ok. Its not brilliant, but costs an
> all.

Have you had a look at what's slowing it down - swapping, contention for
CPU time, other I/O, lack of free RAM for cache due to nearly full RAM,
etc? top and vmstat are your friends. I also find gkrellm _incredibly_
handy for getting a "feel" for load on a system in more general terms
(and it's alerts are incredibly handy, too).

My suspicion: RAM. Get more RAM. RAM is cheap. RAM is good. Get more of
it ;-) . Oh, and if the CPU is a Celeron - I'm sorry. Multitasking is
not their thing, I gather, something to do with the near total lack of
cache. Oh, and if it's a 1.6GHz P4 Celeron, I have a P100 you can have
as a free upgrade.

A dual CPU box does help a lot. I've used my dual PPro/200 as a terminal
server on occasion, and 4 people seem much the same as one to it. I
wasn't asking much of it in terms of workload, though.

While our core server is a dual Xeon with 2 gigs of RAM, it copes very
well with significant numbers of users. I find KDE tends to use about 30
MB for the _first_ KDE user (other users are using XFCE4), less for
subsequent users.

I frequently find that Evolution alone seems to eat more RAM than a full
KDE session. Of course, it's loading large chunks of the GNOME
libraries, so that's more reasonable than it sounds, but still annoying.

> The research I've done onto it suggests a few possible 'solutions'. I'm
> told the preempting in 2.6 works wonders.

It does help, but I wouldn't go so far as to say it's worked wonders for
us. OTOH, our terminal server disk I/O bound not CPU bound (though it
also suffers a bit from low memory due to the sheer amount of things it
has to do).

> I've also garnered that the new
> gnome (also 2.6 I think?!) works much nicer over remote desktop.

KDE 3.2.1 is certainly an incredible improvement. I'd go so far as to
say "jawdropping". I gather a lot of it is improvements in QT, but far
from all. I've been meaning to try GNOME 2.6 over remote X but haven't
found the time to build it yet.

> There does also seem to be much to be said for policy. simple themes (Ie
> the over the top aqua clone is perhaps a nono) and flat wallpaper.
Wallpaper is especially critical, and flat themes do help. I use the
low-color theme and a flat-colour wallpaper on our remote desktops; it
works well. Most users immediately configure photo backgrounds of
course, but even then things seem pretty zippy. (It amazes me the number
of people who can set a desktop background or theme, but still close
programs to "get to the one behind it" instead of minimising/moving.
Priorities, I guess - *sigh*)

A few other helpful things: turn off all menu fades etc, set moves and
resizes to wire-frame mode, disable minimise/maximise animations and
disable icons in menus (including K/foot menu if you have one).

> Wierd spots: Sometimes on KDE , if a couple of terms are logged on same
> user, windows have actually popped up on wrong desktops which is pretty
> whacky.

Not surprising. Some apps may use DCOP to signal new windows rather than
spawning new processes, and this could happen for these. Other apps,
such as Mozilla and OO.o, signal a running process if found - not caring
if it's connected to a different display. I've been known to 'ssh -Xf
remotehost mozilla -mail' and spend a while wondering WTF my mail window
is before clicking that mozilla is running on my local login somewhere
else...

> Evolution doesnt cope. And Mozilla gets wierd locks.
Yup. Only solution: don't log in as the same user on different machines
with a full GUI session. It's annoying, but there's little to be done
about it.

Craig Ringer