[bug#73000] [PATCH] substitutes: Reduce default negative TTL values.

[Maxim Cournoyer]

Hello,

Ludovic Courtès <ludo@gnu.org> writes:

> Hello,
>
> Maxim Cournoyer <maxim.cournoyer@gmail.com> skribis:
>
>> I don't actually have a well formed opinion on the values, but I trust
>> that if Ludo found them annoying, the change must be good.
>
> Yes, for context, these defaults are particularly annoying in the
> context of Cuirass and the Build Coordinator where, if a substitute
> isn’t available at a given point in time, you may want to retry.  For
> this scenario, you’d have to wait for at least 10mn by default because
> ‘guix substitute’ attempts to retry.
>
> Besides, I think I added negative TTLs back in the day to help reduce
> load on substitute servers and to speed up clients in cases where you
> run the same or similar commands several time in a row.  A short TTL can
> be useful, a longer not so much.
>
> At any rate, it doesn’t matter all that much since it’s just a default:
> servers can advertise their own negative TTL, including zero, via the
> ‘Cache-Control’ HTTP header.

Thanks for the explanation; it makes sense.

-- 
Thanks,
Maxim