Commit 89abaf8b authored by Ruediger Pluem's avatar Ruediger Pluem
Browse files

* Introduce environment variable proxy-initial-not-pooled to avoid reusing 

  pooled connections if the client connection is an initial connection.
  This avoids the "proxy: error reading status line from remote server"
  error caused by the race condition that the backend server closed the
  connection after the connection check on our side and before our data
  reached the backend. Yes, this downgrades performance, especially with
  HTTP/1.0 clients. Hence it is configurable and off by default.

PR: 37770


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@684351 13f79535-47bb-0310-9956-ffa450edef68
parent 0b75ec4c

CHANGES

+4 −0
Changes for CHANGES: 4 added lines, 0 removed lines.
Original line number Diff line number Diff line
@@ -2,6 +2,10 @@ 
Changes with Apache 2.3.0

[ When backported to 2.2.x, remove entry from this file ]



  *) mod_proxy_http: Introduce environment variable proxy-initial-not-pooled to

     avoid reusing pooled connections if the client connection is an initial

     connection. PR 37770. [Ruediger Pluem]



  *) mod_proxy: Add connectiontimeout parameter for proxy workers in order to

     be able to set the timeout for connecting to the backend separately.

     PR 45445. [Ruediger Pluem, rahul <rahul sun.com>]

modules/proxy/mod_proxy_http.c

+13 −0
Changes for modules/proxy/mod_proxy_http.c: 13 added lines, 0 removed lines.
Original line number Diff line number Diff line
@@ -1927,6 +1927,19 @@ static int proxy_http_handler(request_rec *r, proxy_worker *worker, 
        ap_proxy_ssl_connection_cleanup(backend, r);

    }



    /*

     * In the case that we are handling a reverse proxy connection and this

     * is not a request that is coming over an already kept alive connection

     * with the client, do NOT reuse the connection to the backend, because

     * we cannot forward a failure to the client in this case as the client

     * does NOT expects this in this situation.

     * Yes, this creates a performance penalty.

     */

    if ((r->proxyreq == PROXYREQ_REVERSE) && (!c->keepalives)

        && (apr_table_get(r->subprocess_env, "proxy-initial-not-pooled"))) {

        backend->close = 1;

    }



    /* Step One: Determine Who To Connect To */

    if ((status = ap_proxy_determine_connection(p, r, conf, worker, backend,

                                                uri, &url, proxyname,

modules/proxy/proxy_util.c

+5 −0
Changes for modules/proxy/proxy_util.c: 5 added lines, 0 removed lines.
Original line number Diff line number Diff line
@@ -2167,6 +2167,11 @@ ap_proxy_determine_connection(apr_pool_t *p, request_rec *r, 
    else {

        conn->addr = worker->cp->addr;

    }

    /* Close a possible existing socket if we are told to do so */

    if (conn->close) {

        socket_cleanup(conn);

        conn->close = 0;

    }



    if (err != APR_SUCCESS) {

        return ap_proxyerror(r, HTTP_BAD_GATEWAY,