From 27c1595cec8606f44d2ec33989daca70cab7d22f Mon Sep 17 00:00:00 2001 From: joey Date: Mon, 13 Aug 2007 06:46:36 +0000 Subject: performance notes --- doc/plugins/write/external.mdwn | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/doc/plugins/write/external.mdwn b/doc/plugins/write/external.mdwn index 735f7a20e..ca30dd229 100644 --- a/doc/plugins/write/external.mdwn +++ b/doc/plugins/write/external.mdwn @@ -86,3 +86,33 @@ use XML RPC for `cgi` or `formbuilder` hooks (which are passed CGI and FormBuilder perl objects), or use it to call `template()` (which returns a perl HTML::Template object). +Also. the `getopt` hook doesn't work, as ARGV is not available to the external +plugin. + +## Performance issues + +Since each external plugin is a separate process, when ikiwiki is +configured to use lots of external plugins, it will start up slower, and +use more resources. One or two should not be a problem though. + +There is some overhead in using XML RPC for function calls. Most plugins +should find it to be pretty minimal though. In one benchmark, ikiwiki was +able to perform 10000 simple XML RPC calls in 11 seconds -- 900 per second. + +Using external plugins for hooks such as `sanitize` and `format`, which +pass around entire pages, and are run for each page rendered, will cause +more XML RPC overhead than usual, due to the larger number of calls, and the +large quantity of data conversion going on. In contrast, `preprocess` hooks +are called generally rarely, and pass around minimal data. + +External plugins should avoid making RPC calls unnecessarily (ie, in a loop). +Memoizing the results of appropriate RPC calls is one good way to minimise the +number of calls. + +Injecting a replacement for a commonly called ikiwiki function +could result in a lot more RPC calls than expected and slow +eveything down. `pagetitle`, for instance, is called about 100 times +per page build. + +In general, use common sense, and your external plugin will probably +perform ok. -- cgit v1.2.3