Re: PATCH: Attempt to make dbsize a bit more consistent

‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐
On Tuesday, 8 September 2020 22:26, David Zhang <david.zhang@highgo.ca> wrote:

>
>
> I found the function "table_relation_size" is only used by buffer
> manager for "RELKIND_RELATION", "RELKIND_TOASTVALUE" and
> "RELKIND_MATVIEW", i.e.
>
>         case RELKIND_RELATION:
>         case RELKIND_TOASTVALUE:
>         case RELKIND_MATVIEW:
>             {
>                 /*
>                  * Not every table AM uses BLCKSZ wide fixed size blocks.
>                  * Therefore tableam returns the size in bytes - but
> for the
>                  * purpose of this routine, we want the number of blocks.
>                  * Therefore divide, rounding up.
>                  */
>                 uint64        szbytes;
>
>                 szbytes = table_relation_size(relation, forkNum);
>
>                 return (szbytes + (BLCKSZ - 1)) / BLCKSZ;
>             }
>
> So using "calculate_relation_size" and "calculate_toast_table_size" in
> "calculate_table_size" is easy to understand and the original logic is
> simple.
>

You are correct. This is the logic that is attempted to be applied
in dbsize.c in this patch.

So what do you think of the patch?