Re: Some comments about GVFS

[Alexander Larsson <alexl redhat com>]

On Tue, 2007-05-08 at 03:33 -0500, Hans Petter Jansson wrote:

> I'm used to three main design patterns:
> 
> 1) Everything in one thread with sync I/O blocking the UI. Simple code
> but unacceptable performance.
> 
> 2) Everything in one thread with async I/O using callbacks. Fine for
> simple protocols or if you prefer an explicit state machine.
> 
> 3) Doing synchronous I/O operations in one or more subthreads that talk
> to the main thread using asynchronous messages queues. This is nice for
> complex protocol implementations, because synchronous code is easier to
> understand and maintain.

These are the main model i see too. But none of these need any main
context but the default mainloop one...

I know Benjamin mentioned multiple contexts was needed for gstreamer
integration. It would be nice to hear some details about this


> I'm aware of the dangers - when I worked on Evolution, this caused
> plenty of pain.
> 
> However, it's useful in very simple apps where you have e.g. a "Sync" or
> "Connect" button which desensitizes most of the UI while the operation
> is in progress, only updating a progress bar or allowing the user to hit
> "Cancel". That's what I meant by a "program that lends itself to that
> design" above :)
> 
> So I dunno. Maybe it's too seductive and should be eliminated as an
> option.

Avoiding this problem is one of the primary reasons of going from a
stateless model (where you can get auth callbacks anytime) to a
statefull model (auth only on mount). However, that problem in gnome-vfs
happens for *all* apps, not only those that "lend itself to that
design", so its a larger problem there.

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 Alexander Larsson                                            Red Hat, Inc 
                   alexl redhat com    alla lysator liu se 
He's an ungodly native American paramedic on the hunt for the last specimen of 
a great and near-mythical creature. She's a wealthy mutant opera singer from 
the wrong side of the tracks. They fight crime!