Re: XMAX_LOCK_ONLY and XMAX_COMMITTED (fk/multixact code)

> On Nov 23, 2021, at 4:51 PM, Bossart, Nathan <bossartn(at)amazon(dot)com> wrote:
>
> This is a good point. Right now, you'd have to manually inspect the
> infomask field to determine the exact form of the invalid combination.
> My only worry with this is that we'd want to make sure these checks
> stayed consistent with the definition of HEAP_XMAX_IS_LOCKED_ONLY in
> htup_details.h. I'm guessing HEAP_XMAX_IS_LOCKED_ONLY is unlikely to
> change all that often, though.

I expect that your patch will contain some addition to the amcheck (or pg_amcheck) tests, so if we ever allow some currently disallowed bit combination, we'd be reminded of the need to update amcheck. So I'm not too worried about that aspect of this.

I prefer not to have to get a page (or full file) from a customer when the check reports corruption. Even assuming they are comfortable giving that, which they may not be, it is an extra round trip to the customer asking for stuff.

—
Mark Dilger
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