Life after LTSP

[Jordan Erickson]

Robert,

I agree with you on your points, but I think you're missing a couple of
things in regard to the bigger picture -

1) Thin clients run at 8-30W of power. Your version of a "power
efficient and fast desktop system" will consume much more than the
average thin client, even if the box says "green" all over it.

2) Flash and Java honestly aren't LTSP's problem. The LTSP devs have
done an AMAZING job at trying to accomidate these types of issues with
proprietary/power hungry softwares, but the fact of the matter is, just
because Flash and/or Java doesn't perform perfectly all the time under
LTSP doesn't mean LTSP isn't a viable solution (Maybe not for your
specific setup though?). Quite the contrary, maybe we should be putting
more pressure on Adobe/Oracle if we want these things to work better as
well? (And on a personal side-rant, Flash is horribly resource intensive
on a standalone workstation, so it really has little to do with LTSP as
a technology - It eats up plenty of CPU on my home PC).

3) Not sure what kind of scenario you mean by scaling full-screen video.
I can run a bluray fullscreen to my LTSP client (not a localapp) with no
lag. Of course that *is* one station and not 50 - but put together some
multicasting magic and I don't see how it could really be a problem, at
least for playing a single video at the same time. If you need to do
many separate videos fullscreen at the same time, a simple
vlc/totem/mplayer localapp will fix that problem straight away. If
you're talking about flash, see #2.

4) Ubuntu != LTSP... Enough said? =)


Just my $0.02!


Cheers,
Jordan


Robert Arkiletian wrote:
> In my opinion,  the days of LTSP are numbered. For a few different reasons.
>
> 1)
> hardware is so cheap now. You can buy a brand new power efficient and
> fast  desktop system for about $200 (not including monitor).  Thin
> clients are actually *more* expensive now.
>
> 2)
> programs like flash and java based apps don't work and will never work
> well in an LTSP environment because they are multithreaded and utilize
> all cores on the server. So no matter how powerful a server, running
> many flash or java apps bring it to it's knees. Things were better
> when all apps were single threaded. As time goes on this will only get
> worse as cpu makers are increasing cores not mhz, so software makers
> are adapting by making apps utilize all cores. Local apps is a
> solution in the right direction but it brings with it other problems
> like using fuse (ltspfs) and other issues. The other problem with
> local apps, in an ltsp client, is that usually true thin client cpu's
> are weak (eg. Atom). The concept of Local apps is 180 degrees to what
> LTSP is about.
>
> 3)
> Things get even worse when you run video full screen because the data
> is being decoded (high cpu hit) at the server, then pushing *large*
> decompressed data across the lan. It just doesn't scale well.
>
> 4)
> If Ubuntu is successful with their move to Wayland display server
> (away from X), LTSP may not even work as Wayland has no network
> transparency as X does. Not sure if having X as a client itself on top
> of Wayland will work with LTSP. My guess is it will be troublesome
> because the client will need Wayland up first before X (which btw
> means it will also definitely need an opengl capable video chipset+driver). I
> suspect that unless the LTSP project goes back to the way they did
> things in LTSP 4, where they pretty much managed and built the chroot
> as a seperate distro, I think Wayland is going to break LTSP with the
> Muekow (LTSP5) way of doing things.
>
> http://www.markshuttleworth.com/archives/date/2010/11
> http://wayland.freedesktop.org/http://wayland.freedesktop.org/
>
> So what do we do? Personally, I think there are at least a couple solutions.
>
> 1)
> Spice. The new remote VM technology that is in Fedora 14 and RHEL6.
> The management gui needs to get better in Fedora, but that's coming.
> Server requirements will be higher than ltsp as each desktop will have
> a VM running (not just a desktop and apps). But advantage will be
> complete customization per client and heterogeneous (windows+linux)
> environments ( at the expense of ease of administration, unless there
> are nice gui tools to manage multiple vm's simultaneously )
>
> 2)
> DRBL. This is the route I have taken. It's similar to ltsp boot
> process via pxe but ALL processes run locally. Only the filesystem is
> remote via nfs. There is no need for special plumbing for sound or
> local devices. Everything works like a stand alone system. Except the
> first time to launch (not run) apps is slightly longer since the
> binary needs to be downloaded into local ram from the network before
> it can be run. One user can't hog ram or cpu. Full class of full
> screen video and flash, no problem. I even have had an entire class of
> students simultaneously install and run Ubuntu in a Virtualbox VM on
> top of  the diskless client OS. Local apps with LTSP cannot do this.
> Although I do have dual gigabit nics for the lan and hardware raid 10
> for the server. Each client can have it's own nfs mounted /etc and
> /var so there can still be customization per client.
>
>