Jan Wieck wrote:
> Computing a checksum just before writing the block will NOT detect any

> faulty memory or Postgres bug that corrupted the block. You will have
a 
> perfectly fine checksum over the corrupted data.
> 
> A checksum only detects corruptions that happen between write and
read. 
> Most data corruptions that happen during that time however lead to
some 
> sort of read error reported by the disk.

I have thought some more about it, and tend to agree now:
Checksums will only detect disk failure, and that's only
one of the many integrity problems that can happen.
And one that can be reduced to a reasonable degree with good
storage systems.

So the benefit of checksums is not enough to bother.

Yours,
Laurenz Albe

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