From: bert hubert Date: Fri, 28 Feb 2014 09:57:03 +0000 (+0100) Subject: remove outdated NPTL advice, add net.ipv6.route.max_size tuning suggestion X-Git-Tag: rec-3.6.0-rc1~158 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d8b721af88a7b4faf1621dc423632619612dd56f;p=thirdparty%2Fpdns.git remove outdated NPTL advice, add net.ipv6.route.max_size tuning suggestion --- diff --git a/pdns/docs/pdns.xml b/pdns/docs/pdns.xml index 369b0f5d28..a7269ad320 100644 --- a/pdns/docs/pdns.xml +++ b/pdns/docs/pdns.xml @@ -6063,7 +6063,7 @@ errors in some cases. Discovered by Sten Spans. Fixed in c1342. PowerDNS now prints out a warning when running with legacy LinuxThreads implementation instead of the high performance NPTL - library, see . c455. + library. c455. @@ -11957,49 +11957,19 @@ local0.err /var/log/pdns.err Authoritative Server Performance General advice - In general, best performance is achieved on recent Linux 2.6 kernels and using MySQL, although many of the largest PowerDNS - installations are based on PostgreSQL. FreeBSD appears to achieve lower packet rates both for the PowerDNS recursor as for the - authoritative nameserver, this is still being investigated. No comparative measurements have been done for Solaris installations. - - - On Linux, make sure to read . + In general, best performance is achieved on recent Linux 3.x kernels and using MySQL, although many of the largest PowerDNS + installations are based on PostgreSQL. FreeBSD also performs very well. Database servers can require configuration to achieve decent performance. It is especially worth noting that several vendors ship PostgreSQL with a slow default configuration. - - - Native Posix Thread Library vs LinuxThreads - - To get the best performance under Linux, especially on SMP - systems, the use of NPTL is advised. The difference in - performance can be over a factor of ten in some circumstances. - - - NPTL is the default library on modern Linux distributions, so - there is generally not a problem, except if you use a - statically compiled version that, for portability reasons, - defaults to LinuxThreads. This includes all .deb and .rpm files - provided by us up to and including 2.9.18. - - - When running a PowerDNS-provided static binary of 2.9.18 or - lower, it may make sense to recompile, or to upgrade to a - newer version, if available. When recompiling, be sure to use - a supported compiler, like g++ >3.2. You might also consider - moving to a distribution supplied version. - - - A good indication that your installation might benefit from - such an upgrade is to watch the 'cs' count in the output of - vmstat 1. If this is very high (> 10000), you are suffering - from a LinuxThreads performance problem called 'overspin'. - - - Thanks are due to L. Bunt Jackson who noted the static - compilation problem in an article in Dr. Dobb's Journal. - + + When deploying (large scale) IPv6, please be aware some + Linux distributions leave IPv6 routing cache tables at very small + default values. Please check and if necessary raise 'sysctl + net.ipv6.route.max_size'. + Performance related settings @@ -14839,6 +14809,12 @@ sql> insert into domainmetadata (domain_id, kind, content) values (6, 'TSIG-ALLO very heavy duty use. + + When deploying (large scale) IPv6, please be aware some + Linux distributions leave IPv6 routing cache tables at very small + default values. Please check and if necessary raise 'sysctl + net.ipv6.route.max_size'. + For older versions <3.2: If you need it, try --fork, this will fork the daemon into two halves, allowing it to benefit from a second CPU.