Additional connections reuse.
If ngx_drain_connections() fails to immediately reuse any connections
and there are no free connections, it now additionally tries to reuse
a connection again. This helps to provide at least one free connection
in case of HTTP/2 with lingering close, where merely trying to reuse
a connection once does not free it, but makes it reusable again,
waiting for lingering close.
diff --git a/src/core/ngx_connection.c b/src/core/ngx_connection.c
index c082d0d..8339e2b 100644
--- a/src/core/ngx_connection.c
+++ b/src/core/ngx_connection.c
@@ -1310,6 +1310,7 @@
cycle->connection_n);
}
+ c = NULL;
n = ngx_max(ngx_min(32, cycle->reusable_connections_n / 8), 1);
for (i = 0; i < n; i++) {
@@ -1326,6 +1327,21 @@
c->close = 1;
c->read->handler(c->read);
}
+
+ if (cycle->free_connection_n == 0 && c && c->reusable) {
+
+ /*
+ * if no connections were freed, try to reuse the last
+ * connection again: this should free it as long as
+ * previous reuse moved it to lingering close
+ */
+
+ ngx_log_debug0(NGX_LOG_DEBUG_CORE, c->log, 0,
+ "reusing connection again");
+
+ c->close = 1;
+ c->read->handler(c->read);
+ }
}
