Gzip Gunzip: always flush busy bufs when the incoming chain is NULL.

[Maxim Dounin]

Hello!

On Fri, Oct 31, 2014 at 06:20:18PM -0700, Yichun Zhang (agentzh) wrote:

> # HG changeset patch
> # User Yichun Zhang <agentzh at gmail.com>
> # Date 1414804249 25200
> #      Fri Oct 31 18:10:49 2014 -0700
> # Node ID 38a74e59f199edafad0a8caae5cfc921ab3302e8
> # Parent  dff86e2246a53b0f4a61935cd5c8c0a0f66d0ca2
> Gzip Gunzip: always flush busy bufs when the incoming chain is NULL.
> 
> After the system send buffer is full, NULL incoming chains are used to
> flush pending output upon new write events. The current gzip and gunzip
> filters may intercept NULL chains and keep the data stalling in
> nginx's own send buffers, leading to request hanging (until send
> timeout).
> 
> This regression had appeared in nginx 1.7.7.

The change is 1.7.7 is intentional, please see 
http://hg.nginx.org/nginx/rev/973fded4f461.

-- 
Maxim Dounin
http://nginx.org/