[Beowulf] from the "I don't remember if its possible" file ...

[Vincent Diepeveen]

Kernel locks every socket action in central manner. Also realtime  
kernel.
Also for RAW/UDP type communication.

So that 'nodelay' is very confusing.

Would need a manufacturer modified kernel (patch) for specific  
network cards to really have no delay.

Removing the lock from the kernel is what would be an interesting  
thing to do yet by default you just can't remove it.

So this might not answer your question - but you will always have  
some sort of delay.


On Mar 22, 2013, at 6:18 PM, Joe Landman wrote:

> Hi folks:
>
>    We are working on something where we can't necessarily change  
> source
> code, but would like to alter the default open parameters of network
> sockets (or a group of network sockets).
>
>    Is there any way to do this in general?  Basically, we want to set
> TCP_NODELAY on a set of applications sockets.  Doesn't have to be in
> general across the machine, and we could probably do this in a  
> cgroup or
> similar construct.  I just don't remember if there is an easy way  
> to do
> this w/o source mods.
>
>    Thanks in advance!
>
> Joe
>
> -- 
> Joseph Landman, Ph.D
> Founder and CEO
> Scalable Informatics, Inc.
> email: landman at scalableinformatics.com
> web  : http://scalableinformatics.com
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>
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