From bc3e713317df838b4bbe6582b357cd8d78e585cd Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ond=C5=99ej=20Sur=C3=BD?= Date: Tue, 2 Jul 2024 20:17:49 +0200 Subject: [PATCH] Throttle the reading when writes are asynchronous Be more aggressive when throttling the reading - when we can't send the outgoing TCP synchronously with uv_try_write(), we start throttling the reading immediately instead of waiting for the send buffers to fill up. This should not affect behaved clients that read the data from the TCP on the other end. --- lib/isc/netmgr/tcp.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/lib/isc/netmgr/tcp.c b/lib/isc/netmgr/tcp.c index 71eee4a2d9..c6bb2812ff 100644 --- a/lib/isc/netmgr/tcp.c +++ b/lib/isc/netmgr/tcp.c @@ -1145,6 +1145,13 @@ tcp_send_direct(isc_nmsocket_t *sock, isc__nm_uvreq_t *req) { } } + isc_log_write(isc_lctx, ISC_LOGCATEGORY_GENERAL, ISC_LOGMODULE_NETMGR, + ISC_LOG_DEBUG(3), + "throttling TCP connection, the other side is not " + "reading the data, switching to uv_write()"); + sock->reading_throttled = true; + isc__nm_stop_reading(sock); + r = uv_write(&req->uv_req.write, &sock->uv_handle.stream, bufs, nbufs, tcp_send_cb); if (r < 0) {