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Re: Weird behavior when using DoH with the multi interface

From: Daniel Stenberg via curl-library <curl-library_at_lists.haxx.se>
Date: Tue, 4 Jun 2024 17:35:34 +0200 (CEST)

On Tue, 4 Jun 2024, Timothe Litt via curl-library wrote:

> The application has no control over how many DNS transactions it takes to
> resolve, e.g. a redirect/cname chain.  So picking a limit would require
> guesswork.

Correct. As a user you also cannot really know how many connections those DNS
transactions will need or create.

Still: the application has decided that it wants libcurl to limit the number
of concurrent connections and presumably such an applications do that for a
reason. So I don't think it is totally unreasonable for libcurl to then
actually try to adhere to that limit, even when DoH is used.

> An alternate approach would be to not count the DOH connections at all - or
> keep a separate cache and/or quota for them.   You probably don't want a
> long-lived libcurl user to keep DOH connections forever, or to cache very
> large numbers.  So a separate limit seems like the right approach.

Sure, but I am not a fan of inventing new complicated schemes if the much
simpler approach works good enough...

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Received on 2024-06-04