ngx_reusable_connection  872 core/ngx_connection.c     ngx_reusable_connection(c, 0);
ngx_reusable_connection  192 core/ngx_connection.h void ngx_reusable_connection(ngx_connection_t *c, ngx_uint_t reusable);
ngx_reusable_connection 2597 http/ngx_http_request.c     ngx_reusable_connection(c, 1);
ngx_reusable_connection 2707 http/ngx_http_request.c     ngx_reusable_connection(c, 0);