(ok 3.3.5) Slow export when having lots of databases

When using phpMyAdmin 3.2.4 with lots of bases (> 6000), it is very slow to export data. there was already improvement after the fix of bug #2832600 but I found out that a bottleneck was the query of the base collation. This is done by querying the information_schema with a
'SELECT DEFAULT_COLLATION_NAME FROM information_schema.SCHEMATA WHERE SCHEMA_NAME = \'' . PMA_sqlAddSlashes($db) . '\' LIMIT 1;'
int the libraries/mysql_charsets.lib.php file around line 165, whether 'DisableIS' is set to 'true' or not.
I tried to using instead code from an older version that speed up the process:
---
if (! $GLOBALS['cfg']['Server']['DisableIS']) {
return PMA_DBI_fetch_value('SELECT DEFAULT_COLLATION_NAME FROM information_schema.SCHEMATA WHERE SCHEMA_NAME = \'' . PMA_sqlAddSlashes($db) . '\' LIMIT 1;');
} else {
PMA_DBI_select_db($db);
$return = PMA_DBI_fetch_value('SHOW VARIABLES LIKE \'collation_database\'', 0, 1);
if ($db !== $GLOBALS['db']) {
PMA_DBI_select_db($GLOBALS['db']);
}
return $return;
}
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