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Re: Couldn't connect to host (err: 7)

From: Daniel Stenberg via curl-library <curl-library_at_cool.haxx.se>
Date: Mon, 21 Sep 2020 18:11:12 +0200 (CEST)

On Mon, 21 Sep 2020, Hadi Rezaee wrote:

> For example in a happy-scenario (no failures - err no 7) and when I reduce
> the REST calls per second to 50 from the client side. I only see 6~8
> established connections (netstat -an | grep 8880) Which is fine.

If each request takes 100ms you should be able to do 50 requests per second
using 5 connections, so with a little rounding errors 6-8 seems within the
margins.

Surely then each connection uses a single easy handle and basically just
reuses the same connection all the time?

> When I increase REST call per second to higher values (300, 400, ..), more
> persistent connections are getting used (which I think it is expected
> right?)

I would imagine each thread would use its own connection and reuse that, yes.
With 10 request/second per thread, you need 70 threads (and connections) for
700 requests/second.

From your description it sounds like it doesn't work quite like that...

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Received on 2020-09-21