Re: error context for vacuum to include block number

On Wed, Mar 04, 2020 at 04:21:06PM +0900, Masahiko Sawada wrote:
> Thank you for updating the patch. But we have two more places where we
> do fsm vacuum.

Oops, thanks.

I realized that vacuum_page is called not only from lazy_vacuum_heap, but also
directly from lazy_scan_heap, which failed to update errcbarg. So I changed to
update errcbarg in vacuum_page.

What about these other calls ? I think granularity of individual function
calls requires a debugger, but is it fine issue if errors here are attributed
to (say) "scanning heap" ?

GetRecordedFreeSpace
heap_*_freeze_tuple
heap_page_prune
HeapTupleSatisfiesVacuum
LockBufferForCleanup
MarkBufferDirty
Page*AllVisible
PageGetHeapFreeSpace
RecordPageWithFreeSpace
visibilitymap_*
VM_ALL_FROZEN

> These functions have LVDeadTuples and LVRelStats but LVDeadTuples can
> be referred by LVRelStats. If we want to use LVRelStats as callback
> argument, we can remove function arguments that can be referred by
> LVRelStats.

That doesn't work easily with parallel vacuum, which passes not
vacrelstats->dead_tuples, but a dead_tuples pulled out of shm_toc.

But it was easy enough to remove "reltuples".

--
Justin