Re: random system table corruption ...

Alvaro Herrera wrote:
> On Sun, Sep 11, 2005 at 01:12:34PM +0200, Hans-Jürgen Schönig wrote:
>
>>in the past we have faced a couple of problems with corrupted system
>>tables. this seems to be a version independent problem which occurs on
>>hackers' from time to time.
>>i have checked a broken file and i have seen that the corrupted page has
>>actually been zeroed out.
>
>
> IIRC the XFS filesystem zeroes out pages that it recovers from the
> journal but did not have a fsync on them (AFAIK XFS journals only
> metadata, so page creation but not the content itself). I don't think
> this would be applicable to your case, because we do fsync modified
> files on checkpoint, and rewrite them completely from WAL images after
> that. But I thought I'd mention it.
>

alvora,

thanks a lot.
we have some reports about sun systems.
meanwhile i got the impression that the filesystem might be doing
something wrong. i have seen that the page is not completely zeroed out.
at some strange positions there are 2 bytes of crap (i have overlooked
that at first glance). the first couple hundreds of bytes are crap,
however. very strange ...

best regards,

hans

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