# HG changeset patch # User Miao Wang <shankerwangm...@gmail.com> # Date 1674055068 -28800 # Wed Jan 18 23:17:48 2023 +0800 # Node ID 73aa64bd29f3dec9e43e97560d6b5a07cdf40063 # Parent 07b0bee87f32be91a33210bc06973e07c4c1dac9 HTTP: trigger lingering close when keepalive connection will be closed
When finalizing a request, if the request is not keepalive but its connection has served more than one request, then the connection has been a keepalive connection previously and this connection will be closed after this response. In this condition, it is likely that there are pipelined requests following this request, which we should ignore. As a result, lingering close is necessary in this case. Without this patch, nginx (with its default configuration) will send out TCP RST when there are more pipelined requests. The symptom is obvious when nginx is serving a debian repository and apt is downloading massive of packages. See [1]. It becomes more obvious when `keepalive_requests` is lower or nginx is under a relative higher load, and it disappears when specifying `lingering_close always`. [1]: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=973861#10 diff -r 07b0bee87f32 -r 73aa64bd29f3 src/http/ngx_http_request.c --- a/src/http/ngx_http_request.c Wed Dec 21 14:53:27 2022 +0300 +++ b/src/http/ngx_http_request.c Wed Jan 18 23:17:48 2023 +0800 @@ -2749,6 +2749,10 @@ return; } + if (!r->keepalive && r->connection->requests > 1) { + r->lingering_close = 1; + } + if (clcf->lingering_close == NGX_HTTP_LINGERING_ALWAYS || (clcf->lingering_close == NGX_HTTP_LINGERING_ON && (r->lingering_close _______________________________________________ nginx-devel mailing list nginx-devel@nginx.org https://mailman.nginx.org/mailman/listinfo/nginx-devel
