We are running DB2 8.2 on RHEL 3, on a Compaq DL380 G3. Tablespaces are on one mirrored disk pair, the backup directory is on another. Disks are standard Compaq 15K, 36GByte, hotswap, scsi connected.
Backups of small databases (backup files c120 Mbytes) take about 7 minutes. There is no real difference between offline and online backups at times of low database usage.
Simply coping the files between the two file systems, from a Linux shell, takes 3-4 seconds (same speed copying the files in either direction). Looking at the file modofication times, the backup files are created in the first few seconds of the backup. This is consistent with the backup timestamp.
However, the target filesystem continues to be thrashed at about 95% usage for the whole of 7 minutes that the backup appears to take. Can anyone explain what is going on in this period?
Thanks
Martyn Hodgson
Backups of small databases (backup files c120 Mbytes) take about 7 minutes. There is no real difference between offline and online backups at times of low database usage.
Simply coping the files between the two file systems, from a Linux shell, takes 3-4 seconds (same speed copying the files in either direction). Looking at the file modofication times, the backup files are created in the first few seconds of the backup. This is consistent with the backup timestamp.
However, the target filesystem continues to be thrashed at about 95% usage for the whole of 7 minutes that the backup appears to take. Can anyone explain what is going on in this period?
Thanks
Martyn Hodgson