Re: [xml] libxml2 thread safety

["Jon Smirl" <jonsmirl mediaone net>]

Xerces offers a fully thread safe parser and DOM. It is also one of the
slowest DOMs in existence. This DOM is especially slow on SMP machines where
every memory alloc and DOM access involves a multi-CPU thread lock.

Xalan was originally built using the Xerces DOM. Xalan has since replaced
the Xerces DOM with it's own internal DOM and only uses Xerces for SAX-like
events.

Currently Xerces and Xalan have a single static initialization which needs
to be thread safe. All other global information it is stored in processor
objects which are private to a thread.

In general adding thread safety was a very bad experience on Xerces/Xalan.
This is much better handled at a higher level.

Jon Smirl
jonsmirl mediaone net