Backup is too slow - configuration?

Hi, we have an HP Surestore dlt vs80e and use hp dlt IV tapes (capacity 40/80GB) under linux. But the backup is to slow, we should have a backup rate of 10.8 GB (native)/20.6 (comprimized), but we do not have :-( So i have some questions, to which i did not find answers until now! In the file

When amanda begins to flush?

Hi, thank you for your first answer. One question again: Amanda creates the files in the holding disk, when does Amanda begin to write it out to tape? When the first file is created or when all files are created? In the first case, there can be a short time period where the tape has to be