Re: invalid page header

Markus Schiltknecht <markus@bluegap.ch> writes:
>> Block 58591 ********************************************************
>> <Header> -----
>> Block Offset: 0x1c9be000         Offsets: Lower    12858 (0x323a)
>> Block: Size 28160  Version   73            Upper    14900 (0x3a34)
>> LSN:  logid 627535472 recoff 0x3a693b22      Special  9506 (0x2522)
>> Items: 3209                   Free Space: 2042
>> Length (including item array): 8192
>>
>> Error: Invalid header information.

Hm, looks suspiciously ASCII-like.  If you examine the page as text,
is it recognizable?  We've seen cases where, for instance, a page
of a system's mail spool had replaced a database page.  It's hard to
be sure whether that sort of thing is a hardware error or an operating
system bug.

> What's the best cure? Can I just wipe out the block with something like:
> # dd if=/dev/zero of=base/296788/302602 seek=58591 bs=8192 count=1

Yeah, try that.  I think the net effect will be that some wide (toasted)
values will be truncated.

            regards, tom lane