Re: [DOC] Add detail regarding resource consumption wrt max_connections - Mailing list pgsql-hackers

From Cary Huang
Subject Re: [DOC] Add detail regarding resource consumption wrt max_connections
Date
Msg-id 170509767861.1131.15083983626399995184.pgcf@coridan.postgresql.org
Whole thread Raw
In response to [DOC] Add detail regarding resource consumption wrt max_connections  (Roberto Mello <roberto.mello@gmail.com>)
Responses Re: [DOC] Add detail regarding resource consumption wrt max_connections
Re: [DOC] Add detail regarding resource consumption wrt max_connections
List pgsql-hackers
The following review has been posted through the commitfest application:
make installcheck-world:  tested, passed
Implements feature:       tested, passed
Spec compliant:           tested, passed
Documentation:            tested, passed

I think it is good to warn the user about the increased allocation of memory for certain parameters so that they do not
abuseit by setting it to a huge number without knowing the consequences.
 

It is true that max_connections can increase the size of proc array and other resources, which are allocated in the
sharedbuffer, which also means less shared buffer to perform regular data operations. I am sure this is not the only
parameterthat affects the memory allocation. "max_prepared_xacts" can also affect the shared memory allocation too so
thesame warning message applies here as well. Maybe there are other parameters with similar effects. 
 

Instead of stating that higher max_connections results in higher allocation, It may be better to tell the user that if
thevalue needs to be set much higher, consider increasing the "shared_buffers" setting as well.
 

thank you

-----------------------
Cary Huang
Highgo Software Canada
www.highgo.ca

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