Incredible slow loading on admin/manage_resources.php page

[vuongkienthanh]

I installed successfully on a xubuntu desktop, everything works fine, except for the admin/manage_resources.php only show initial page then wait loading the resource listing and button group. While waiting, the add resource button doesn't function. So it takes about 3 min until I can add more resources.

I already tried $conf['settings']['schedule']['fast.reservation.load'] = 'true';

This also happens in the demo.