From 3ffe979334962d6f4d1d9f020a47b5ddc73350bd Mon Sep 17 00:00:00 2001 From: Otto Date: Sun, 28 Nov 2021 09:20:31 +0100 Subject: [PATCH] Warn about blocking calls from Lua --- pdns/recursordist/docs/lua-scripting/index.rst | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/pdns/recursordist/docs/lua-scripting/index.rst b/pdns/recursordist/docs/lua-scripting/index.rst index a93d215055..cd56c8d828 100644 --- a/pdns/recursordist/docs/lua-scripting/index.rst +++ b/pdns/recursordist/docs/lua-scripting/index.rst @@ -2,8 +2,6 @@ Scripting PowerDNS Recursor =========================== In the PowerDNS Recursor, it is possible to modify resolving behaviour using simple scripts written in the `Lua `_ programming language. -**Note**: This describes the Lua scripts as supported by 4.x. They are very different than the ones from 3.x, but tend to be faster and more correct. - These scripts can be used to quickly override dangerous domains, fix things that are wrong, for load balancing or for legal or commercial purposes. The scripts can also protect you or your users from malicious traffic. @@ -13,6 +11,11 @@ If you already have programming experience, `Learn Lua in 15 Minutes `_ is supported. +.. note:: + PowerDNS Recursor is capable of handling many queries simultaneously using cooperative user space multi-threading. + Blocking functions called from Lua are not cooperative, they will monopolize a worker thread while being blocked. + Avoid blocking calls. + .. toctree:: :maxdepth: 2 -- 2.47.2