From: Sebastian Harl Date: Mon, 26 Nov 2007 11:19:17 +0000 (+0100) Subject: collectd-perl(5): Replaced "BUGS" with "CAVEATS" section. X-Git-Tag: collectd-4.3.0beta0~76 X-Git-Url: https://git.verplant.org/?a=commitdiff_plain;h=07136fdb92194dde56720e9e1465dcf6f9c32fbd;p=collectd.git collectd-perl(5): Replaced "BUGS" with "CAVEATS" section. The bugs section is no longer relevant, however, the users should be warned about some (mostly Perl ithread specific) limitations. Signed-off-by: Sebastian Harl Signed-off-by: Florian Forster --- diff --git a/src/collectd-perl.pod b/src/collectd-perl.pod index ffe5177d..760e5da3 100644 --- a/src/collectd-perl.pod +++ b/src/collectd-perl.pod @@ -404,12 +404,38 @@ To register those functions with collectd: See the section "DATA TYPES" above for a complete documentation of the data types used by the read and write functions. -=head1 BUGS +=head1 CAVEATS -This plugin does not yet work correctly if collectd uses multiple threads. -Perl does not allow multiple threads to access a single interpreter at the -same time. As a temporary workaround you should use a single read thread only -(see collectd's B configuration option). +=over 4 + +=item + +collectd is heavily multi-threaded. Each collectd thread accessing the perl +plugin will be mapped to a Perl interpreter thread (see L). +Any such thread will be created and destroyed transparently and on-the-fly. + +Hence, any plugin has to be thread-safe if it provides several entry points +from collectd (i.Ee. if it registers more than one callback). Please +note that no data is shared between threads by default. You have to use the +B module to do so. + +=item + +Each function name registered with collectd has to be available before the +first thread has been created (i.Ee. basically at compile time). This +basically means that hacks (yes, I really consider this to be a hack) like +C<*foo = \&bar; plugin_register (TYPE_READ, "plugin", "foo");> most likely +will not work. This is due to the fact that the symbol table is not shared +across different threads. + +=item + +Each plugin is usually only loaded once and kept in memory for performance +reasons. Therefore, END blocks are only executed once when collectd shuts +down. You should not rely on END blocks anyway - use B +instead. + +=back =head1 SEE ALSO @@ -417,6 +443,8 @@ L, L, L, L, +L, +L, L =head1 AUTHOR