Backup size is not correct on both server and gui

i have urbackup that used to backup alot of server in my environment i start to observer that backup page for each clinet is showing wrong info regarding size for example if i take today backup on activity it start loading till reach 1.5 TB but on screen it show only 30 GB and when i browse to server file and du -hs current day folder of this client i found size is same as shown in backup page but there is hidden directory .directory_pool taken around 1.4TB any advise on what is the issue here