[pgpool-general: 2299] Re: Pool queue length

[Tatsuo Ishii]

Probably you misunderstand the description of the manual.

> Nobody wants to touch this one?
> 
> I get the feeling this queue isn't managed by PGPOOL, can anyone confirm or
> deny?
> 
> Cheers,
> James Sewell
> 
> On Wednesday, 30 October 2013, James Sewell wrote:
> 
>> Hello All,
>>
>> The documentation states:
>>
>> "Up to 2*num_init_children can be queued"
>>
>> I assumed this to mean that if I set num_init_children to 2, then I can
>> field 2 client connections (one to each forked process) at a time. The
>> third and fourth connections will be queued, then the fifth will be
>> rejected.
>>
>> However this doesn't seem to be the reality. I can demonstrate this with
>> psql, opening many more than 4 connections. The first two connect, the next
>> x idle waiting for a connection.

Yes, that's the expected behavior and does nothing to do with OS's
queue. If your case the third and fourth psql are waiting for accepted
in the kernel queue. If there's are too many clients waiting for
connection, the queue is overflow and the client gets error.
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese: http://www.sraoss.co.jp

>> I saw another similar post which said:
>>
>> "... it is up to OSs behavior when pgpool set backlog parameter"
>>
>> Could someone explain this a bit more? Where is the backlog parameter?
>>
>> Is there a way I can check this queue length so I can alarm on it?
>>
>> Cheers,
>>
>>
>> James Sewell,
>> PostgreSQL Team Lead / Solutions Architect
>> ______________________________________
>>
>>
>>  Level 2, 50 Queen St, Melbourne VIC 3000
>>
>> *P *(+61) 3 8370 8000  *W* www.lisasoft.com  *F *(+61) 3 8370 8099
>>
>>
> 
> 
> -- 
> 
> James Sewell,
> PostgreSQL Team Lead / Solutions Architect
> ______________________________________
> 
> 
>  Level 2, 50 Queen St, Melbourne VIC 3000
> 
> *P *(+61) 3 8370 8000  *W* www.lisasoft.com  *F *(+61) 3 8370 8099
> 
> -- 
> 
> 
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