Re: [Fab-user] _fanout_strategy status & other stuff

[Christian Vest Hansen]

On Mon, Oct 20, 2008 at 3:57 PM, Sylvain BLOT <address@hidden> wrote:
> I saw inside the source code
> that _fanout_strategy is currently broken. What's the problem? How can I/dev
> fix it? ( I've some python experiences)

The problem is blocking-IO + GIL.

The paramiko channels must be set to non-blocking mode, then execute
(start) the remote command and collect the output from all hosts with
select() or polling.

Trouble is that you need to do a bit of refactoring to _on_hosts_do()
and the whole strategies setup. And this will also affect the commands
that need to do IO on paramiko channels.

So the current design of those internals is actually broken, with
regards to implementing something like fanout mode.

On Mon, Oct 20, 2008 at 10:19 PM, Jeff Forcier <address@hidden> wrote:
> I think we just haven't had the time or need to get parallel execution
> working yet. The source code has an old attempt by Christian but I
> believe it had some problems. I don't recall what those were.

If you're thinking of prototypes/ctr-c.py, then that was an attempt at
building a super-duper-awesome (like > (sum cap dsh clusterssh))
replacement for `fab shell` but it grew too complex and fragile, and
that's where I left it.

On Mon, Oct 20, 2008 at 10:19 PM, Jeff Forcier <address@hidden> wrote:
> If you're any good with threading or similar techniques, feel free to
> make your own fork of the project via GitHub and see if you can get it
> working. Otherwise, I will probably give it a shot sometime in the
> semi near future -- I have a branch which has made serious changes to
> the overall execution of Fab commands, and adding true parallelism
> would be the next big step.

Yes, it would be really nice to finally get this to work. It's
probably the most prominent non-existing feature in fabric. :)

On Mon, Oct 20, 2008 at 3:57 PM, Sylvain BLOT <address@hidden> wrote:
> An other think is that I will need a Web Gui for my fabric scripts, do you
> have any development recommendations (webservice, os.run()...) ?

I have never tried to do something like that.

-- 
Venlig hilsen / Kind regards,
Christian Vest Hansen.