Re: how to plan for vacuum?

Just have one example here:

workload: run pgbench in 365x24x7
database size: 100GB

the workload distribution:
06:00-24:00 100tps
00:00-06:00 20tps

how should we plan vacuum for this situation to get the highest performance?

Best regards
Galy

Galy Lee wrote:
> Hi,
>
> For I can not find too much information about how to use vacuum, I want
> to ask some general information about the guideline of vacuum planning.
>
> 1. How do we know if autovacuum is enough for my application, or should
> I setup a vacuum manually from cron for my application?
>
> 2. How to set the GUC parameters for autovacuum?
> There are two sets of parameters for autovacuum:
> - vacuum threshold and scale factor (500/0.2)
> 　 - analyze threshold and scale factor(250/0.1)
> Is there any guideline to set these parameters? When does it need to
> change the default values?
> 　
> 3. How to tune cost-based delay vacuum?
> I had searched in performance list; it seems that most of the practices
> are based on experience / trial-and-error approach to meet the
> requirement of disk utilization or CPU utilization. Is there any other
> guild line to set them?
>
> For when autovacuum is turned on by default, if the parameters for
> vacuum have not been set well, it will make the system rather unstable.
> So I just wonder if we should setup a section in the manual about the
> tips of vacuum, then many users can easily set the vacuum parameters for
> their system.