Re: Few comments on commit 857f9c36 (skip full index scans )

On Mon, May 28, 2018 at 4:52 AM, Amit Kapila <amit.kapila16@gmail.com> wrote:
> Hi,
>
> Review comments on commit 857f9c36:
> 1.
> @@ -2049,6 +2055,10 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf)
>     metapg = BufferGetPage(metabuf);
>     metad = BTPageGetMeta(metapg);
>
> +   /* upgrade metapage if needed */
> +   if (metad->btm_version < BTREE_VERSION)
> +       _bt_upgrademetapage(metapg);
> +
>
> The metapage upgrade should be performed under critical section.
>
> 2.
> @@ -191,6 +304,10 @@ _bt_getroot(Relation rel, int access)
>         LockBuffer(metabuf, BUFFER_LOCK_UNLOCK);
>         LockBuffer(metabuf, BT_WRITE);
>
> +       /* upgrade metapage if needed */
> +       if (metad->btm_version < BTREE_VERSION)
> +           _bt_upgrademetapage(metapg);
> +
>
> Same as above.
>
> In other cases like _bt_insertonpg, the upgrade is done inside the
> critical section.  It seems the above cases are missed.
>
> 3.
> +   TransactionId btm_oldest_btpo_xact; /* oldest btpo_xact among of
> +                                        * deleted pages */
>
> /among of/among all
>
> Attached patch to fix the above comments.
>

Thank you for reviewing and the patch. All changes looks good to me.

Regards,

--
Masahiko Sawada
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center