Re: Difference between "autovacuum_naptime" and"autovacuum_vacuum_cost_delay"?

On 08/16/2018 09:42 PM, Raghavendra Rao J S V wrote:
> Thank you very much for your response.
> 
> Could you clarify me below things,please?

The docs can:

https://www.postgresql.org/docs/10/static/routine-vacuuming.html#AUTOVACUUM

https://www.postgresql.org/docs/10/static/runtime-config-autovacuum.html

> 
> What is the difference between "autovacuum_naptime" and 
> "autovacuum_vacuum_cost_delay"?
> 
> What is the difference between "autovacuum launcher process" and 
> "autovacuum worker process"?
> 
> How to control the number of "autovacuum launcher process" and 
> "autovacuum worker process"?
> 
> Does "autovacuum launcher process" sleeps? If yes,which parameter 
> controls it?
> 
> Does "autovacuum worker process" sleeps? If yes,which parameter controls it?
> 
> Regards,
> Raghavendra Rao
> 
> 
> On 17 August 2018 at 09:30, Joshua D. Drake <jd@commandprompt.com 
> <mailto:jd@commandprompt.com>> wrote:
> 
>     On 08/16/2018 06:10 PM, Raghavendra Rao J S V wrote:
>>     Hi All,
>>
>>     I have gone through several documents but I am still have
>>     confusion related to "autovacuum_naptime" and
>>     "autovacuum_vacuum_cost_delay". Could you clarify me with an example.
>>
>>     When Auto vacuum worker process will start?
>>
> 
>     Autovacuum checks for relations that need to be vacuumed/analyzed
>     every "naptime"
> 
>>     When Auto vacuum worker process will stop?
> 
>     When it is done with the list of relations that needed work that
>     were found at the launch of "naptime"
> 
>>
>>     Does Auto vacuum worker process will sleep like Auto vacuum
>>     launcher process ?
> 
>     The launcher process sleeps for naptime, then wakes up to check what
>     needs to be worked on
> 
>>
>>     What is the difference between Auto vacuum launcher process and
>>     Auto vacuum worker process?
> 
>     The launcher is the process that spawns the worker processes (I think).
> 
>     JD
>>
>>
>>
>>     -- 
>>     Regards,
>>     Raghavendra Rao J S V
>>
> 
>     -- 
>     Command Prompt, Inc. ||http://the.postgres.company/  || @cmdpromptinc
>     ***  A fault and talent of mine is to tell it exactly how it is.  ***
>     PostgreSQL centered full stack support, consulting and development.
>     Advocate: @amplifypostgres || Learn:https://postgresconf.org
>     *****     Unless otherwise stated, opinions are my own.   *****
> 
> 
> 
> 
> -- 
> Regards,
> Raghavendra Rao J S V
> Mobile- 8861161425


-- 
Adrian Klaver
adrian.klaver@aklaver.com