how to use multiple remote displays

[Martin Drautzburg]

Vadim Zeitlin wrote:

>  There is an extra/missing 0 or two somewhere, 30MB*500 is more like 15GB.

You're right

>  And, of course, if you actually need 20 shared MB per user and 10 MB per
> instance it becomes "only" 5GB.

I was hoping for shared data too. I looked at the VmRss value in KDE System
Guard which showed 30 MB. Also I tried to start 40 instances and my 500 MB
RAM machine ate up 1500 MB (with 1000 MB in swap). This fits in nicely with
the estimated 30 MB per instance.

It was still impressing to see that it still worked.

> MD> (1) Is it possible to access multiple remote DISPLAYs from different
> threads MD> of the same process and if so: how ?
> 
>  It should be but I honestly don't think you're going to gain much except
> the possibility of having many new and exciting bugs by doing it. Using
> multiple threads doesn't magically reduce the memory consumption, although
> it can reduce the numbers shown by ps.

If my users sit on another machine than the one I control, then per-session
STATE must be saved somewhere. 

The WEB-application folks claim that they are working stateless but they
have to reintroduce state by all sorts of dirty tricks, like cookies and
hidden variables. Because it is cumbersome to manage STATE in this world,
STATE is automatically minimzed. Also much of the state is kept at the
client, so the Gigabytes of required RAM are distributed over a large
number of computers. Thus it becomes possible to service a large user base
at the cost of difficult development and poor look and feel.

In the X11 world all this is much more straightforward, but I did not expect
STATE to cost me as much as 30 MB per user.

I keep thinking that there must be a technical solution to this problem (the
political aspects will still remain difficult). I can't see a vital point
why it should not be possible to do straightforward application development
(i.e. without writing html and doing low-level programming) and still be
able to service many remote users. 

I keep wondering why the computing world has added all sorts of bells and
whistels to their web Browsers but has not yet solved this obvious issue. I
could not even find ATTEMPTS to do this (well maybe the squeak plugin), so
I may be completely off the track.