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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