From: Remi Gacogne Date: Tue, 12 Jan 2021 14:46:07 +0000 (+0100) Subject: dnsdist: Apply Pieter's suggestions to the tuning guide X-Git-Tag: dnsdist-1.6.0-alpha1~24^2~2 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=43d8a234aff6a4580d36d564d407c54095ceaccc;p=thirdparty%2Fpdns.git dnsdist: Apply Pieter's suggestions to the tuning guide --- diff --git a/pdns/dnsdistdist/docs/advanced/tuning.rst b/pdns/dnsdistdist/docs/advanced/tuning.rst index 345a57fea4..692f14979d 100644 --- a/pdns/dnsdistdist/docs/advanced/tuning.rst +++ b/pdns/dnsdistdist/docs/advanced/tuning.rst @@ -69,8 +69,12 @@ For DNS over HTTPS, every :func:`addDOHLocal` directive adds a new thread dealin When dealing with a large traffic load, it might happen that the internal pipe used to pass queries between the threads handling the incoming connections and the one getting a response from the backend become full too quickly, degrading performance and causing timeouts. This can be prevented by increasing the size of the internal pipe buffer, via the `internalPipeBufferSize` option of :func:`addDOHLocal`. Setting a value of `1048576` is known to yield good results on Linux. When dispatching UDP queries to backend servers, dnsdist keeps track of at most **n** outstanding queries for each backend. -This number **n** can be tuned by the :func:`setMaxUDPOutstanding` directive, defaulting to 10240 (65535 since 1.4.0), with a maximum value of 65535. -Large installations are advised to increase the default value at the cost of a slightly increased memory usage. +This number **n** can be tuned by the :func:`setMaxUDPOutstanding` directive, defaulting to 65535 which is the maximum value. + +.. versionchanged:: 1.4.0 + The default was 10240 before 1.4.0 + +Large installations running dnsdist before 1.4.0 are advised to increase the default value at the cost of a slightly increased memory usage. Lock contention and sharding ----------------------------