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As we can see in these tests storing recovery data on checkpoint can give performance boost (throughput) about 3-5% in normal cases and up to 2x in extreme cases with heavy disk load. But checkpoint time also increases about twice. Since half of the checkpoint time checkpoint buffer pages can't be released it leads to excessive checkpoint buffer usage, compared to approach with storing recovery data in WAL physical records. High checkpoint buffer usage enables throttling to protect from checkpoint buffer overflow. Old throttling algorithm (exponential backoff) is not suitable for new approach of storing recovery data, on the first phase of checkpoint it can completely stop all page modifying threads until recovery data written, so, the new throttling algorithm (based on fill rate of checkpoint buffer) for the new approach has been implemented and used in benchmarks.

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