The production journal holds redo log buffers until the logs are transferred to the recovery server. Then, the logs are available to receive new application write data.
The goal of sizing the production journal properly is to prevent the recovery server from falling so far behind the production server that dynamic recovery must occur for the recovery server to catch up. If the production journal is too small, then transfers between the production server and the recovery server are performed more frequently than is efficient.
The appropriate size of the production journal is proportional to one of the following:
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No-impact downtime: The length of network or recovery server downtime that Assure MIMIX for AIX can sustain without falling into dynamic recovery.
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The amount of data in throughput spikes that exceed system bandwidth that Assure MIMIX for AIX can sustain without falling into dynamic recovery