Bonjour Michaël,
I agree that having a server function (extension?) to do a full checksum
verification, possibly bandwidth-controlled, would be a good thing. However
it would have side effects, such as interfering deeply with the server page
cache, which may or may not be desirable.
In what is that different from VACUUM or a sequential scan?
Scrubbing would read all files, not only relation data? I'm unsure about
what does VACUUM, but it is probably pretty similar.
It is possible to use buffer ring replacement strategies in such cases
using the normal clock-sweep algorithm, so that scanning a range of
pages does not really impact Postgres shared buffer cache.
Good! I did not know that there was an existing strategy to avoid filling
the cache.
--
Fabien.
