Re: make MaxBackends available in _PG_init - Mailing list pgsql-hackers

From Fujii Masao
Subject Re: make MaxBackends available in _PG_init
Date
Msg-id 01c32f6c-8101-1ce4-8295-534cf067df94@oss.nttdata.com
Whole thread Raw
In response to Re: make MaxBackends available in _PG_init  ("Bossart, Nathan" <bossartn@amazon.com>)
Responses Re: make MaxBackends available in _PG_init
List pgsql-hackers

On 2021/08/16 13:02, Bossart, Nathan wrote:
> On 8/15/21, 1:05 AM, "wangsh.fnst@fujitsu.com" <wangsh.fnst@fujitsu.com> wrote:
>> I don't think calling function GetMaxBackends() in the for loop is a good idea.
>> How about use a temp variable to save the return value of function GetMaxBackends() ?
> 
> I did this in v4.  There may be a couple of remaining places that call
> GetMaxBackends() several times, but the function should be relatively
> inexpensive.

The patch handles only MaxBackends. But isn't there other variable having the same issue?

It seems overkill to remove "extern" from MaxBackends and replace MaxBackends with GetMaxBackends() in the existing
PostgreSQLcodes. I'm not sure how much it's actually worth doing that.  Instead, isn't it enough to just add the
commentlike "Use GetMaxBackends() if you want to treat the lookup for uninitialized MaxBackends as an error" in the
definitionof MaxBackends?
 

Regards,

-- 
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION



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