Re: Lock contention high - Mailing list pgsql-performance

From Jeremy Schneider
Subject Re: Lock contention high
Date
Msg-id 9a440edd-f0b3-c95b-7b87-4204daff9bd5@ardentperf.com
Whole thread Raw
In response to Lock contention high  (Ashkil Dighin <ashkildighin76@gmail.com>)
Responses Re: Lock contention high
List pgsql-performance
Your settings are interesting, I'm curious what the goal is for this
particular hammerdb exercise.

A few comments inline


On 10/12/21 00:35, Ashkil Dighin wrote:
> 
> Postgres.conf used  in Baremetal
> ========================
> maintenance_work_mem = 512MB           

only a half GB memory for autovac? (it will have a mandatory run as soon
as you hit 200 mil XIDs, seems like you'd want the full max 1GB for it)

> synchronous_commit = off            
> checkpoint_timeout = 1h         
> checkpoint_completion_target = 1       
> checkpoint_warning = 0         

curious about this, seems you're just looking to understand how much
throughput you can get with a config that would not be used on a real system

> autovacuum = off                       

i assume you understand that autovacuum will still run when you hit 200
mil XIDs. this setting seems incongruent with the previous settings,
because it seemed like you were going for throughput, which generally
requires autovacuum to be more aggressive rather than less aggressive.
assuming the benchmark runs for a properly sufficient length of time,
this setting will slow things down because of accumulating bloat.

Just a few opinions, I might be wrong, hope the feedback is helpful.  :)

-Jeremy


-- 
http://about.me/jeremy_schneider



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