> To be perfectly clear: I have actually seen bug reports trace to
> problems that I think a block-level CRC might have detected (not
> corrected, of course, but at least the user might have realized he had
> flaky hardware a little sooner). So I do not say that the upside to
> a block CRC is nil. But I am unconvinced that it exceeds the
> downside, in development effort, runtime, false failure reports
> (is that CRC error really due to hardware trouble, or a software bug
> that failed to update the CRC? and how do you get around the CRC error
> to get at your data??) etc etc.
Something to remember: currently we update t_infomask (set
HEAP_XMAX_COMMITTED etc) while holding share lock on buffer -
we have to change this before block CRC implementation.
Vadim