Re: Bug (#3484) - Invalid page header again

Gregory Stark <stark@enterprisedb.com> writes:
> I don't understand this 9728 bytes. Postgres blocks are 8192 bytes. Are you
> saying one whole block is trashed and then part, but not all, of the next
> block?

> What's the block size of the ZFS filesystem? And what exactly does the trash
> data look like?

It seems relevant that 9728 is a multiple of 512 (and not of any larger
power of 2).  That makes it sound like the misfeasance happened at the
disk block level.  Postgres doesn't internally deal in 512-byte chunks
anywhere I can think of, so to posit a DB bug you have to come up with
some other explanation why exactly that much of the block got trashed.

A filesystem-level software bug is not out of the question, though
this still smells to me like it's a hardware issue of some kind.

            regards, tom lane