Re: Detecting corrupted pages earlier

Tom Lane kirjutas T, 18.02.2003 kell 17:21:
> Kevin Brown <kevin(at)sysexperts(dot)com> writes:
> > Tom Lane wrote:
> >> The cases I've been able to study look like the header and a lot of the
> >> following page data have been overwritten with garbage --- when it made
> >> any sense at all, it looked like the contents of non-Postgres files (eg,
> >> plain text), which is why I mentioned the possibility of disks writing
> >> data to the wrong sector.
>
> > That also sounds suspiciously like the behavior of certain filesystems
> > (Reiserfs, for one) after a crash when the filesystem prior to the
> > crash was highly active with writes.

I was bitten by it about a year ago as well.

> Isn't reiserfs supposed to be more crash-resistant than ext2, rather
> than less so?

It's supposed to be, but when it is run in (default?)
metadata-only-logging mode, then you can well get perfectly good
metadata with unallocated (zero-filled) data pages. There had been some
more severe errors as well.

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Hannu