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From: Fred Pedrisa <fredhps10@hotmail.com>
To: "'freebsd-current'" <freebsd-current@FreeBSD.org>
Subject: Select() vs Netmap
Date: Sun, 1 Jun 2014 13:38:34 -0300
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Hey, guys.

 

 

I'm currently experiencing a strange issue in my program (Using netmap).

 

Sometimes, when I call select() in a FD, it gets like 4~8 packets per event,
however suddenly it drops to 1~2 packets per event, losing a lot of
performance and increasing the number of select calls necessary to poll the
NIC for new packets.

 

Is there any type of tweak I can do, to make this behavior becomes linear
and sustain the performance in such case without these oscillations ?

 

The behavior happens under the same stressing circumstances, around 1.4
Mpps~ (64 byte packets).

 

 

Sincerely,

 

Fred