I think that's PHP developper knows what they do but the limit is too low... perhaps we could try to make a workaround on the next install.php of dokuwiki...
that will test version of PHP, and if it >= 5.2 then bring a warning on the 'pcre.backtrack_limit' ...
For the rest there is a stack overflow relative to this library... it is why they put this limits on pcre... and i don"t know if there is no regression on this implementation so ... wait to see, try to increase amount ... and vote on the bug tracker :
http://bugs.php.net/bug.php?id=40846
I build a small script to test this workaround with your test page :
<php>
list($major, $minor, $rev) = split('[\..-]', phpversion_real());
echo "Your PHP version is : Major: $major; Minor: $minor; Revision: $rev<br />\n";
if ($major >= 5 ) {
if ($minor >= 2 ) {
echo "You could have a problem in parsing large Dokuwiki Page.<br />\n";
$backtrap = ini_get("pcre.backtrack_limit");
echo "Your php.ini pcre.backtrack_limit is : $backtrap<br />\n";
if ($backtrap<=100000){
echo "Your pcre.backtrack_limit is too low, try to increase it to at least 20971520<br />\n";
}
if ($backtrap>=20971520){
echo "Your pcre.backtrack_limit seems to be in good order for a better DokuWiki experience<br />\n";
}
}}
function phpversion_real()
{
$v = phpversion();
$version = Array();
foreach(explode('.', $v) as $bit)
{
if(is_numeric($bit))
{
$version[] = $bit;
}
}
return(implode('.', $version));
}
</php>
the full source with your test page could be copy from there :
http://jm.massou.free.fr/dokuwiki/doku.php?id=test_large_page&do=edit&rev=