下面这个是范围。
结合自己的环境可以用RecoveryPoint Calculator这个工具来计算。也可以用下面这个公式人为计算,不过还是建议用工具。
1.05*[(data per second)*(required rollback time in seconds)/(1-target side log size)]+reserved for marking
注:这个公式适用于没有snapshot consolidation的情况。一般来说,日志卷要保留20% for the target side log and 5% for virtual access data structures
举个例子:
data per second = 5 Mb/s
required rollback time = 24 hr = 86 400 s
image access log = 0.20
reserved for marking = 1.5 GB
那么:
1.05 * 5 Mb/s * 86 400 s / (1 - 0.20) + 1.5 GB = 579 000 Mb
579 000 Mb = 579 000/8 MB = 72 375 MB = 72.4 GB
你可以用 iostat (UNIX) or perfmon (Windows) 来确定data per second.
默认的image access log size is 20%.
下面这个是范围。
结合自己的环境可以用RecoveryPoint Calculator这个工具来计算。也可以用下面这个公式人为计算,不过还是建议用工具。
1.05*[(data per second)*(required rollback time in seconds)/(1-target side log size)]+reserved for marking
注:这个公式适用于没有snapshot consolidation的情况。一般来说,日志卷要保留20% for the target side log and 5% for virtual access data structures
举个例子:
data per second = 5 Mb/s
required rollback time = 24 hr = 86 400 s
image access log = 0.20
reserved for marking = 1.5 GB
那么:
1.05 * 5 Mb/s * 86 400 s / (1 - 0.20) + 1.5 GB = 579 000 Mb
579 000 Mb = 579 000/8 MB = 72 375 MB = 72.4 GB
你可以用 iostat (UNIX) or perfmon (Windows) 来确定data per second.
默认的image access log size is 20%.