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<div>Hi all,</div>
<div><br>
</div>
<div>we're having a streaming replication setup as backend for one of our client's application we're hosting.</div>
<div>The backend consists of two virtual machines (Fedora Server 25) running PostgreSQL 9.6 and Pgpool 3.6.4 (this also happened with previous Pgpool versions).</div>
<div><br>
</div>
<div>Those machines are configured for streaming replication in master/slave mode. The Postgres-Instances are running fine, but Pgpool is giving us troubles.</div>
<div><br>
</div>
<div>After some time, Pgpool stops accepting connections. They are not rejected, the application trying to connect simply hangs. I have to stop the corresponding Pgpool-Instance</div>
<div>and the other takes over. The stopping itself takes forever. After some time, systemd simply kills the processes and I have to manually delete the leftover sockets.</div>
<div><br>
</div>
<div>I have absolutely no idea what's causing this. The Postgres-Instances are configured to accept up to 1000 connections, which should not be the problem.</div>
<div><br>
</div>
<div>About the application accessing the database:</div>
<div><br>
</div>
<div>There are multiple instances, each using a separate database. The application uses Activiti, which DOES NOT pool connections. So we're having a pretty high amount of</div>
<div>connections per second. The problem mostly occurs during peak hours, so load is most likely a factor. </div>
<div><br>
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<div>I've tried plaing around with num_init_children and max_pool. Increasing max_pool and lowering num_init_children made things a lot worse.</div>
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<div>Also, Pgpool still accepts pool join requests from other Pgpool instances, it's just that database connections aren't handled anymore.</div>
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<div>You can find my pgpool.conf here: <a href="https://pastebin.com/4ee2bhhf">https://pastebin.com/4ee2bhhf</a></div>
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<div>Regards,</div>
<div>Thomas</div>
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