Many connections get SYN_RECV status

Posted April 29, 2014 13.6k views
I have small app, client connects to socket (socket listened by twisted based socket server), send/receive some data, disconnects and reconnects in 2 second. While I was on another VPS, it was ok, but now connections too often get SYN_RECV status. I'm not system administrator, so used default Ubuntu image. I have tried config sysctl, use many solutions from internet but cannot get positive result.

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2 answers
Thenks, I will read this article, but it's about 10 open connections at the same time, i think ~1000 open close operation/min.
I have googled for a week before ask the question.
Looks like your droplet is receiving too many connections, check out You can read more on that by googling "Linux TCP/IP optimization."