Subject: C-Ares obeys strict DNS query-reply order on the wire?

C-Ares obeys strict DNS query-reply order on the wire?

From: Fred Huang <divfor_at_gmail.com>
Date: Thu, 29 Nov 2012 16:34:57 +0800

hi all,

Recently I found 8 threads of curl-loader that uses libcurl as well as
libcares can only do DNS queries one by one in the wire. tcpdump shows they
are all query-reply peer in strict packets order. I think this is the root
cause why the max speed is 350 queries/s.

however, adns can reach 10,000 queries/s (adnhost +e -a -f < hostlist)
against same dnsmasq server, measured by tcpdump.

so, is there something/option libcurl can do to have cares to send a block
of queries each time? or this just is by design?

thanks,
Fred

Received on 2012-11-29