Re: Write visibility map during CLUSTER/VACUUM FULL

On Sun, Sep 1, 2019 at 1:37 PM Alexander Korotkov
<a.korotkov@postgrespro.ru> wrote:
>
> Hi!
>
> I found it weird that CLUSTER/VACUUM FULL don't write visibility map.
> Attached patch implements writing visibility map in
> heapam_relation_copy_for_cluster().
>
> I've studied previous attempt to implement this [1].  The main problem
> of that attempt was usage of existing heap_page_is_all_visible() and
> visibilitymap_set() functions.  These functions works through buffer
> manager, while heap rewriting is made bypass buffer manager.
>
> In my patch visibility map pages are handled in the same way as heap
> pages are.
>

I haven't studied this patch in detail, but while glancing I observed
that this doesn't try to sync the vm pages as we do for heap pages in
the end (during end_heap_rewrite).  Am I missing something?

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