Re: postgresql9.4 aws - no pg_upgrade

> On 2 Nov 2017, at 23:03, bala jayaram <balajayaram22(at)gmail(dot)com> wrote:
>
> Hi Team,
>
>
> We tried in production, pg_upgrade works well. But running vacuumdb , resulted in huge spike in CPU, system halted. Is there a way to fasten or parallel vacuum solution for faster recovery after pg_upgrade.
>
> Our database size is around 500GB, contains multiple databases, huge records. What is the minimum way to do a vacuuming after pg_upgrade? This is for migration from 9.3 to 9.4.

All you need to do right after the upgrade is getting new statistics by running "analyze" or by doing something like vacuumdb -a -v -z.
That should take a while but it shouldn't "halt" anything. I believe that 9.4 doesn't have -j in vacuumdb, so you can script
something that will will get all tables, split them and run each part in X number of psqls.
When you are done with the statistics then scheduling a vacuum would be a good idea. this can be done during any convenient
time or you can just split the work using a script.

Regards,
Vasilis Ventirozos