Re: [Proposal] Fully WAL logged CREATE DATABASE - No Checkpoints

On Mon, Dec 6, 2021 at 9:17 AM Ashutosh Sharma <ashu(dot)coek88(at)gmail(dot)com> wrote:
>
> Here are few more review comments:

Thanks for reviewing it.

> 1) It seems that we are not freeing the memory allocated for buf.data in CreateDirAndVersionFile().

Yeah this was a problem in v6 but I have fixed in v7, can you check that.
>
> + */
> +static void
> +CreateDirAndVersionFile(char *dbpath, Oid dbid, Oid tsid, bool isRedo)
> +{
>
> 2) Do we need to pass dbpath here? I mean why not reconstruct it from dbid and tsid.

Yeah we can do that but I thought computing dbpath has some cost and
since the caller already has it why not to pass it.

>
> 3) Not sure if this point has already been discussed, Will we be able to recover the data when wal_level is set to minimal because the following condition would be false with this wal level.
>
> + use_wal = XLogIsNeeded() &&
> + (relpersistence == RELPERSISTENCE_PERMANENT || copying_initfork);
>

Since we are creating new relfilenode this is fine, refer "Skipping
WAL for New RelFileNode" in src/backend/access/transam/README

--
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com