Re: error context for vacuum to include block number

On Tue, Mar 17, 2020 at 9:52 AM Amit Kapila <amit.kapila16@gmail.com> wrote:
>
>
> Another minor point, don't we need to remove the error stack by doing
> "error_context_stack = errcallback.previous;" in parallel_vacuum_main?
>

Few other comments:
1. The error in lazy_vacuum_heap can either have phase
VACUUM_ERRCB_PHASE_INDEX_* or VACUUM_ERRCB_PHASE_VACUUM_HEAP depending
on when it occurs.  If it occurs the first time it enters that
function before a call to lazy_vacuum_page, it will use phase
VACUUM_ERRCB_PHASE_INDEX_*, otherwise, it would use
VACUUM_ERRCB_PHASE_VACUUM_HEAP.  The reason is lazy_vacuum_index or
lazy_cleanup_index won't reset the phase after leaving that function.

2. Also once we set phase as VACUUM_ERRCB_PHASE_VACUUM_HEAP via
lazy_vacuum_page, it doesn't seem to be reset to
VACUUM_ERRCB_PHASE_SCAN_HEAP even when we do scanning of the heap.  I
think you need to set phase VACUUM_ERRCB_PHASE_SCAN_HEAP inside loop.

I think we need to be a bit more careful in setting/resetting the
phase information correctly so that it doesn't display the wrong info
in the context in an error message.

-- 
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com