Friday, March 21, 2008

More Good News (Ubuntu Community Support is Still Great) and Bad News (Using Flash on LTSP Will Evidently Cost Me More Money)

Well I've already got a response to my question about flash player being so slow. This is due to the amazing support from the Ubuntu (and Edubuntu specifically) community that I've continually received. What follows is a transcript of the first response I received to my listserv post. Of course I'll be sure to post here tomorrow about the steps I took and the results they gave. Cheers! (and thanks for the help Robert!) -joe

> I'm having the same problem as Uwe with flash being slow. In this flash game
> (I use it to help my kinders practice using the mouse) I can literally see
> the frames refreshing and it is utterly unusable. I got my gigabit uplink
> switch today and connected it but there was no change from the old 10/100
> switch I was using before. The new switch should just work out of the box
> right? The LED indicates it has a gigabit connection. Since this made no
> difference I also did a clean install of Hardy Beta hoping to see some
> change. Alas.
>
>Here is a link to the system monitor display after I hooked up the switch
> but before the Hardy install. I would say this image is typical of what I've
> seen with 5 thin clients running the aforementioned flash game whether in
> Gutsy or Hardy with Gigabit or not (although the RAM and CPU is running a
> bit high since I had just opened firefox on a couple machines before I took
> the screenshot).
>
> The server is a Dell GX270 P4 running at 3 GHz. It seems like the whole
> server slows down when flash is playing, but I haven't confirmed this. With

You have multiple reasons for the poor performance.
1) You have a weak server. It is not even dual cpu. Old netburst architecture.
2) You don't have much ram. 1GB is only enough for about 7 clients.
3) make sure you are running without ssh overhead for X. ( enable direct X )
4) even if you get a fast server and do all the tweaking I'm afraid
that site is still going to be slow

LTSP is not good at streaming video AND sound to thin clients. Network
latency, remote X, high cpu usage for many clients just doesn't work
well. It can get better than what you currently have but it will never
be like running the browser locally (on the client). If you have
powerful enough clients (min P3 800 + 256MB) check this out.

https://help.ubuntu.com/community/UbuntuLTSP/LTSPFatClients

> Hardy the game is even slow on the server, although this was not the case
> with Gutsy (BTW Hardy seems realllllllly slow to log in on the server. Like
> Gutsy on my laptop. Not good.) I've tried different thin clients with no
> changes. I've also tried Cat 5 and 6 cables to the clients with no change. I
> haven't tried Gnash in a while so I could give that a shot, but that still
> doesn't solve the real problem.

BTW Gnash just release 0.8.2.

>
> Is the network activity supposed to peak and valley like that? It does this
> even if I'm doing something other than flash, like a google docs or

All your X display traffic is flowing through your network.

1 comment:

Unknown said...

Hi Joseph!
I saw your presentation at CUe in Palm Springs. Just dropped by your blog and wanted to say hi! Great blog - sorry to hear about Flash on the thin clients. Congrats on the new switch! You mentioned the switch thing in your presentation. Thanks for posting all of this info, it's so valuable for anyone interested in thin clients, Ubuntu in the classroom, etc.

-Kristen