On Tue, Sep 29, 2009 at 11:32:32AM -0400, zhijianpeng wrote:

> I found that :
>
> #define NGX_LISTEN_BACKLOG 511
>
> and use it as the backlog of listen()
>
> ls.backlog = NGX_LISTEN_BACKLOG;
> if (listen(s, ls.backlog) == -1) {
>
> Does it mean that only 511 connection could be accept at the same time ?

No, it means that up to 511 connections can be queued in kernel listen
queue. 511 is just a safe limit for the most OSes. For FreeBSD it's -1,
i.e., value of sysctl kern.ipc.somaxconn.

> May I modify it to 1024 or higher( I am sure use it less than SOMAXCONN )

listen 80 default backlog=1024;


--
Igor Sysoev
http://sysoev.ru/en/