I know how checkpointing works in Postgres (which isn't very different from how it works in most other redo-log implementations). It still does not change that you need to actually update the heap at some point.
Postgres allows a group commit to try to combine multiple transactions to avoid the multiple fsyncs, but it adds delay and is off by default. And even so, it reduces fsyncs, not writes.
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I know how checkpointing works in Postgres (which isn't very different from how it works in most other redo-log implementations). It still does not change that you need to actually update the heap at some point.
Postgres allows a group commit to try to combine multiple transactions to avoid the multiple fsyncs, but it adds delay and is off by default. And even so, it reduces fsyncs, not writes.