Re: Bug in new buffer freelist code - Mailing list pgsql-hackers

From Jan Wieck
Subject Re: Bug in new buffer freelist code
Date
Msg-id 3FE8B266.3070102@Yahoo.com
Whole thread Raw
In response to Re: Bug in new buffer freelist code  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Bug in new buffer freelist code  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Tom Lane wrote:

> BTW, I just managed to reproduce the hang, after a whole afternoon of
> trying ... only it was with a non-debug build.  Sigh.  Anyway, it seems
> my HP machine has a significantly higher probability of showing the
> problem than my Linux machine --- I have been unable to see the problem
> in thirty or forty "make checks" on that one.
> 
> Let me know if there's any test I could run to confirm your theory,
> assuming I can make it happen again after I finish rebuilding.

You could add another assertion that checks that the CDB found is 
actually pointing to the buffer that is being invalidated.

Looking at the bufmgr.c code for FlushRelationBuffers() ... it does 
exactly what I described ... leaving the relnode and buffernum for an 
invalidated buffer just where they are.


Jan

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