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<== Date ==> <== Thread ==>

Subject: Re: Dropped frames from GigE cameras on Linux
From: Henrique Almeida <[email protected]>
To: Mark Rivers <[email protected]>
Cc: "[email protected] Talk" <[email protected]>
Date: Sat, 23 Apr 2016 16:08:20 -0300

It's better not to change rmem_default, or most sockets in the system will have an increased buffer size. Instead, using setsockopt() will increase the buffer size only for the camera.

Also, a 1 MB buffer may not be enough, since it represents a 8 ms buffer in a 1 Gbps network. It is common for an application to be preempted for dozens of milliseconds under heavy load. I'm currently testing 2 MB for our non-GigE camera server. Our camera, however, does not support packet retransmissions, while the GigE protocol does.

Em 21/04/2016 15:19, "Mark Rivers" <[email protected]> escreveu:

Folks,

 

I find that people frequently have problems with dropped frames when running GigE cameras on Linux, particularly under heavy CPU loading. 

 

In 2013 I posted a message to tech-talk (http://www.aps.anl.gov/epics/tech-talk/2013/msg02491.php) about this problem.  It contained a link from Tom Cobb to a Point Grey Knowledge Base article with a solution, which involves increasing some system values as follows:

 

sudo sysctl -w net.core.rmem_max=1048576 net.core.rmem_default=1048576

 

I  found today that the Point Grey link in that message no longer works.  However, here is a new link that does work.

 

http://www.ptgrey.com/KB/10016

 

Mark

 

 


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RE: Dropped frames from GigE cameras on Linux Mark Rivers
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Dropped frames from GigE cameras on Linux Mark Rivers

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