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RE: SMTP Performance of cUrl

From: Patrick Monnerat <>
Date: Tue, 18 Oct 2011 13:45:57 +0200

Daniel Stenberg wrote:
>> The problem is when I send email from the module, it takes around 4-5

>> seconds to receive "354 Start mail input; end with <CRLF>.<CRLF>" and

>> state goes from RCTP to DATA. My question is if this is a normal time

> I don't think it is normal - a server should be able to respond more
or less instantly. But since you wait for the server's response it is
nothing libcurl can do anything about.

In fact it may be normal: by configuration, some SMTP servers wait some
seconds after connect before sending the connect answer and discard
everything from a client beginning to "talk" before this initial reply.
This is a very efficient anti-spam disposition :-) See

For the current problem, I would check the SMTP dialog timeline from the
connection, and perform some tests against another server...


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Received on 2011-10-18