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From: Jim Nasby <[email protected]>
To: jarek <[email protected]>
To: [email protected]
Subject: Re: Big number of connections
Date: Sun, 3 Apr 2016 12:18:59 -0500
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
References: <[email protected]>
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On 4/1/16 2:54 AM, jarek wrote:
> I'll be happy to hear form users of big PostgreSQL installations, how
> many users do you have and what kind of problems we may expect.
> Is there any risk, that huge number of roles will slowdown overall
> performance ?

The red flag from your original email was concern over each connection 
consuming 1MB of memory. If you're so tight on memory that you can't 
afford 4GB of backend-local data, then I don't think you'll be happy 
with any method of trying to handle 4000 concurrent connections.

Assuming you're on decent sized hardware though, 3000-4000 open 
connections shouldn't be much of an issue *as long as very few are 
active at once*. If you get into a situation where there's a surge of 
activity and you suddenly have 2x more active connections than cores, 
you won't be happy. I've seen that push servers into a state where the 
only way to recover was to disconnect everyone.
-- 
Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX
Experts in Analytics, Data Architecture and PostgreSQL
Data in Trouble? Get it in Treble! http://BlueTreble.com


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