Assuming the
before-image block size is (or will be) the same as the
after-image block size,
before-image writes can be used to determine approximately how many after-image blocks will be written.
To understand the network bandwidth requirements for each Replication Environment during peaks of high activity, the maximum network bandwidth can be
estimated with the following formula:
Replication_Bandwidth = 1.5 * BI (writes per second at peak time) * (BI block size) = # bytes / second
Example:
1. PROMON > R&D > 2 (Activity Displays) > 5 (BI Log):
Activity Displays Menu
1. Summary
2. Servers
3. Buffer Cache
4. Page Writers
5. BI Log
2. Gather metrics on the
Total BI writes per second:
Activity: BI Log
Total Per Min Per Sec Per Tx
Total BI writes 151 906 150.10 0.70
3. Calculate the Replication
Bandwidth:Assuming the BI block size is 16 KBytes,
Replication_Bandwidth = 1.5 * 150.10 writes/sec * 16 KBytes/write = 3,602.4 KBytes/sec
OpenEdge Replication sends approximately 3.5 MB/sec of data to the target database during peak activity.
To calculate the communications bandwidth requirement you need to convert to bits/second like this:
3,602.4 KBytes/sec * 8 bits/Byte = 28,819.2 Kbits/sec = 28.14 Mbits/sec or 28.14 Mbps
