Questions on backend allocations

[Dridi Boukelmoune]

Hi,

It turned out you couldn't properly create backends dynamically, or at
least remove them. Please find attached a patch set that fixes that,
and adds a "director" capability to the debug vmod with an initial
test case. This is still incomplete, and I want to push this further. For
example I've created a Backend_added log record, but nothing for
deletion.

Before I do anything else, I'll wait for feedback :)

Cheers,
Dridi

PS. today I'm doing training and the customer is blocking IRC

On Thu, Mar 19, 2015 at 12:26 AM, Dridi Boukelmoune <dridi at varni.sh> wrote:
> Hi,
>
> As discussed briefly during the last VDD in Hamburg, phk said that
> everything should be in place to allow dynamic backend allocations
> (ie. outside of pure VCL).
>
> I looked quickly at the code right after the VDD with fgs, and at the
> time there was a couple backend-related commits that had just showed
> up. But I came to the conclusion that you could only add/remove a
> backend and a tcp pool in vcl_init and vcl_fini.
>
> Those operations can only be triggered by the CLI thread right now, so
> it's not possible to programmatically add a backend at any arbitrary
> time and still benefit from the existing facilities (stats, probes,
> connection pools, etc).
>
> I haven't made any progress since then, so I'm asking first what the
> comment was about. I think I misunderstood what it was supposed to
> mean at the time.
>
> Also please find attached a tiny patch removing leftovers I found after the
> VDD.
>
> Regards,
> Dridi
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