Re: performance of pg_upgrade "Copying user relation files"

On 10/2/19 3:30 PM, Glenn Pierce wrote:
> I have been trying to upgrade postgres 9.5 to 9.6 with pg_upgrade
>
> Everything seems to start fine but when pg_upgrade gets to "Copying
> user relation files"
> It takes ages to complete copying.

This is going to need more information:

1) What is the pg_upgrade command you are using?

2) Where are you upgrading from/to?

3) What OS, version?

>
> ie
> Each file like
>
> /var/lib/pgsql/9.5/data/base/24602/25140
> is 1G and taking ~5-10 minutes to copyand that directory is 223G of
> about 990 files
>
> After a couple of hours running pg_upgrade I had to give up.
>
> looking a iotop I was seeing
>
> 99% IO load caused by [md0_raid1]
>
> and only seeing pg_upgrade go to 99% every 3-4 seconds
>
> I had no other processes using io or high cpu.
>
> Has anyone got any pointers of what could be the issue ?
>
> Ps running cp on /var/lib/pgsql/9.5/data/base/24602/25140 to my home
> directory is instantaneous
>
> System is Centos 7
>
> Thanks
>
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com