Re: Order of operations in lazy_vacuum_rel

Tom Lane wrote:

> Actually, after thinking about this some more, I realize that this code
> has got a significantly bigger problem than just whether it will respond
> to CANCEL promptly. If we truncate the table, and then get an error
> sometime before commit, the relcache inval message will not be sent,
> leaving other backends at significant risk of strange errors due to
> having rd_targblock pointing somewhere past the end of the table.
> So we should reorder these operations just to reduce the risk window,
> and I've done so.

Err, that problem was exactly why I added the interrupt holdoff in
there, so if you've got a better/more invasive solution, it's very
welcome.

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Alvaro Herrera http://www.CommandPrompt.com/
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