[K12OSN] 64 bit ltsp vs. virtualization

[Julius Szelagiewicz]

On Mon, 23 Jun 2008, Luis Montes wrote:

> Nils Breunese wrote:
> > Luis Montes wrote:
> >
> >> I'm placing an order today for a new server. The school I'm using it
> >> at has about 75 thin clients.
> >> Currently we're using an smbldap serer and two dual-core 4GB ram
> >> servers.
> >>
> >> I'm gonna spend 5 or 6 K today on a 64bit 8-core 16GB ram monster.
> >> (well monster compared to what I have right now)
> >>
> >> Now I'd like to just add this new box to the network as another ltsp
> >> server using 64 bit edubuntu or fedora+ltsp, but so far my couple of
> >> months with a 64 bit desktop have me thinking this might not be the
> >> best approach.
> >>
> >> The main problem I have is that Adobe's has yet to get off their
> >> butts and product a 64bit flash plugin. I know I can use the
> >> nspluginwrapper but it only seems to work about half the time, and
> >> when it does work, half the time sound doesn't.  I imagine that sound
> >> through the thin clients will be even more troublesome.
> >>
> >> The other option I have is to load centos5.1 or ubuntu 8.04 on the
> >> new server and something like vmware server to slice it up with 4 or
> >> so 32bit guests.
> >>
> >> That second option seems like a waste of resources, but it may give
> >> me less headaches.
> >>
> >> Surely there are other ltsp users in the same boat right now?
> >> Thoughts?
> >
> > I have a quadcore with 4 GB RAM loaded with K12LTSP 5EL 64-bit. We do
> > run into those issues with Flash being 32-bit only (crashes with
> > nspluginwrapper and 32-bit Flash under 64-bit Firefox, although you
> > can install 32-bit Firefox only) and no 64-bit Java browser plugin
> > being available. You should be able to use 16 GB RAM with the PAE
> > kernel on 32-bit Linux (up to 64 GB according to
> > http://en.wikipedia.org/wiki/Physical_Address_Extension).
> >
> Thanks for the reply.  32-bit with PAE seems the easiest route to take.
> I get the feeling I'm not fully utilizing my hardware, though all i
> really wanted the 64bit cores was for the additional ram.
>
> I'll give this route a shot and let the list know how it went. If anyone
> cares :)
>
> Luis

There is a dramatic change in speed between the apps compiled for 64bit
and 32bit. I'd suggest to run as much 64bit software as possible to gain
full advantage of the server. The 64bit kernel alone is going to make a
huge difference - direct memory access, faster script and utilities
execution add up very quickly. Look at your most frequently used apps and
try to run them in 64bit executables - Firefox excluded, because of the
plugins and crashing problems.

julius