NGX_SPDY_SYN_REPLY_SIZE  521 src/http/ngx_http_spdy_filter_module.c                                      + NGX_SPDY_SYN_REPLY_SIZE
NGX_SPDY_SYN_REPLY_SIZE  528 src/http/ngx_http_spdy_filter_module.c     b->last += NGX_SPDY_FRAME_HEADER_SIZE + NGX_SPDY_SYN_REPLY_SIZE;