Change initial TCP send window size

Yair · 06-08-2009, 04:08 AM

Hi,

I am working on a project to change the initial send window size under different scenarios. Looking at tcp capture I see that the sender always sends 2 packets. I am working on kernel 2.6.29.1.

I was digging in the kernel source code and added congestion control module. I thought the place to change it is the function .init. So I changed the snd_cwnd to 4 but still no luck, the sender sends 2 packets.

I am new to kernel development, any ideas how to control the send windows size?

Mara · 06-10-2009, 03:34 PM

Are you sure snd_cwnd is 4 when the packets are sent? When you have this checked, I'd also look into the tcp_init_congestion_ops structure.