> On 19 Mar 2026, at 23:11, Heikki Linnakangas <hlinnaka@iki.fi> wrote:
>
> :-(. This is a gift that keeps giving.
Well, maybe, we could leaving that deadlock in place for some time...
> Idea 3:
>
> I think a better fix is to accept that our tracking is a little imprecise and use SimpleLruDoesPhysicalPageExist() to
checkif the page exists. I suspect that's too expensive to do on every RecordNewMultiXact() call that crosses a page,
butperhaps we could do it once at StartupMultiXact().
>
> Or perhaps track last-zeroed page separately from latest_page_number, and if we haven't seen any
XLOG_MULTIXACT_ZERO_OFF_PAGErecords yet after startup, call SimpleLruDoesPhysicalPageExist() to determine if
initializationis needed. Attached patch does that.
SimpleLruDoesPhysicalPageExist() does not detect recently zeroed pages via buffers, because it goes directly to FS.
I tried this approach when implementing deadlock fix, it did not work for me.
Best regards, Andrey Borodin.
