DataGuard in RAC and redo apply performance in consolidated environments
My customer has five standby databases in the same 2-node RAC cluster. Today, after an ASM data diskgroup full, several databases had to recover quite some archivelogs.
The load on the first node immediately went to the roof when I restarted the redo apply, after adding space to the diskgroup.
This because, by default, the redo apply starts on the first available instance of the RAC cluster, which in this case was the first instance for all DBs.
Two things I learned:
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