Increasing send buffer with sysctl

bpottle · 07-05-2006, 01:16 PM

Currently running Fedora Core 5, 2.6.15

I'm running a program from the flow-tools package that generates sample data and sends it to a socket. However, when I execute it, I get a string of messages reading:

Code:

flow-send: send(): Message too long
flow-send: send(): Message too long
flow-send: send(): Message too long

I'm assuming this is the EMSGSIZE kernel error from the Googling I've done. This is the output I currently get for the two relevant settings (according to what I'm reading)

Code:

[root@starbuck]# sysctl net.core.rmem_max
  net.core.rmem_max = 80000000
[root@starbuck]# sysctl net.ipv4.tcp_wmem
  net.ipv4.tcp_wmem = 4096    65536    8388608

I'm not sure of the exact message size it's trying to send, but all I want to do is increase my settings to the point where they're large enough to allow it through -- so a ridiculous overshot is fine, I'm just not sure how to enter the command. Which do I change, and how?

Thanks,
--Ben

bpottle · 07-05-2006, 01:45 PM

I'm not sure if it's relevant or not... but I'm actually running a collector right before this to receive the data I'm generating, and it looks like it issues some socket-related command when it runs:

Code:

[root@starbuck]# ./flow-receive 0/0/2055 | ./flow-print
flow-receive: setsockopt(size=4194304)
...(listening)

--Ben