From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Zhangjie (HZ)" <zhangjie14@huawei.com>
Subject: [QA-TCP] How to send tcp small packages immediately?
Date: Fri, 24 Oct 2014 15:41:17 +0800
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Hi,

I use netperf to test the performance of small tcp package, with TCP_NODELAY set :

netperf -H 129.9.7.164 -l 100 -- -m 512 -D

Among the packages I got by tcpdump, there is not only small packages, also lost of
big ones (skb->len=65160).

IP 129.9.7.186.60840 > 129.9.7.164.34607: tcp 65160
IP 129.9.7.164.34607 > 129.9.7.186.60840: tcp 0
IP 129.9.7.164.34607 > 129.9.7.186.60840: tcp 0
IP 129.9.7.164.34607 > 129.9.7.186.60840: tcp 0
IP 129.9.7.186.60840 > 129.9.7.164.34607: tcp 65160
IP 129.9.7.164.34607 > 129.9.7.186.60840: tcp 0
IP 129.9.7.164.34607 > 129.9.7.186.60840: tcp 0
IP 129.9.7.164.34607 > 129.9.7.186.60840: tcp 0
IP 129.9.7.186.60840 > 129.9.7.164.34607: tcp 80
IP 129.9.7.186.60840 > 129.9.7.164.34607: tcp 512
IP 129.9.7.186.60840 > 129.9.7.164.34607: tcp 512

SO, how to test small tcp packages? Including TCP_NODELAY, What else should be set?

Thanks!
-- 
Best Wishes!
Zhang Jie