On Mon, Jun 4, 2018 at 9:46 AM, Fujii Masao <masao.fu...@gmail.com> wrote:
> Generally the recovery performance of DROP DATABASE is not critical > for many users. But unfortunately my colleague's project might need to > sometimes drop the database using multiple tablespaces, for some reasons. > So, if the fix is not so complicated, I think that it's worth applying > that. > Agree, in isolation need for this improvement is not felt, but yes any improvements for single serialized replay process is definitely helpful. > The straight approach to avoid such unnecessary scans is to change > DROP DATABASE so that it generates only one XLOG_DBASE_DROP record, > and register the information of all the tablespace into it. Then, WAL > replay > of XLOG_DBASE_DROP record scans shared_buffers once and deletes > all tablespaces. POC patch is attached. > Also, irrespective of performance improvement looks better to just have single xlog record for the same.
