details: https://hg.nginx.org/nginx/rev/cffaf3f2eec8 branches: changeset: 8125:cffaf3f2eec8 user: Maxim Dounin <mdou...@mdounin.ru> date: Thu Feb 02 23:38:48 2023 +0300 description: Lingering close for connections with pipelined requests.
This is expected to help with clients using pipelining with some constant depth, such as apt[1][2]. When downloading many resources, apt uses pipelining with some constant depth, a number of requests in flight. This essentially means that after receiving a response it sends an additional request to the server, and this can result in requests arriving to the server at any time. Further, additional requests are sent one-by-one, and can be easily seen as such (neither as pipelined, nor followed by pipelined requests). The only safe approach to close such connections (for example, when keepalive_requests is reached) is with lingering. To do so, now nginx monitors if pipelining was used on the connection, and if it was, closes the connection with lingering. [1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=973861#10 [2] https://mailman.nginx.org/pipermail/nginx-devel/2023-January/ZA2SP5SJU55LHEBCJMFDB2AZVELRLTHI.html diffstat: src/core/ngx_connection.h | 1 + src/http/ngx_http_request.c | 4 +++- 2 files changed, 4 insertions(+), 1 deletions(-) diffs (32 lines): diff -r f5515e727656 -r cffaf3f2eec8 src/core/ngx_connection.h --- a/src/core/ngx_connection.h Sat Jan 28 05:23:33 2023 +0300 +++ b/src/core/ngx_connection.h Thu Feb 02 23:38:48 2023 +0300 @@ -172,6 +172,7 @@ struct ngx_connection_s { unsigned timedout:1; unsigned error:1; unsigned destroyed:1; + unsigned pipeline:1; unsigned idle:1; unsigned reusable:1; diff -r f5515e727656 -r cffaf3f2eec8 src/http/ngx_http_request.c --- a/src/http/ngx_http_request.c Sat Jan 28 05:23:33 2023 +0300 +++ b/src/http/ngx_http_request.c Thu Feb 02 23:38:48 2023 +0300 @@ -2753,7 +2753,8 @@ ngx_http_finalize_connection(ngx_http_re || (clcf->lingering_close == NGX_HTTP_LINGERING_ON && (r->lingering_close || r->header_in->pos < r->header_in->last - || r->connection->read->ready))) + || r->connection->read->ready + || r->connection->pipeline))) { ngx_http_set_lingering_close(r->connection); return; @@ -3123,6 +3124,7 @@ ngx_http_set_keepalive(ngx_http_request_ c->sent = 0; c->destroyed = 0; + c->pipeline = 1; if (rev->timer_set) { ngx_del_timer(rev); _______________________________________________ nginx-devel mailing list nginx-devel@nginx.org https://mailman.nginx.org/mailman/listinfo/nginx-devel
