Re: connection dropped from the backend server

> On Mar 27, 2018, at 6:49 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
> Adrian Klaver <adrian(dot)klaver(at)aklaver(dot)com> writes:
>> On 03/27/2018 04:07 PM, armand pirvu wrote:
>>> As long as the connection stays up yes data gets fine across
>>> In pg_stat_activity I see the node ip address where tail -f piped into psql happens
>
>> So what does the rest of that record show? In particular for:
>
> I wonder how often data gets put into the pipe. If it's "not very often",
> maybe the connection from psql to the server is timing out due to
> inactivity? This would be the fault of a firewall or something in
> between. You could probably fix it by enabling (more aggressive) TCP
> keepalive settings.
>
> regards, tom lane

Well there is no flow pattern, The flow can be inexistent for days , even weeks and then it can get super busy

The data flows as expected well untill the connection gets dropped. Bolded from pg_stat_activity (a test I just did)

birstdb=# select datname, pid, client_addr, client_port, backend_start, query_start, state from pg_stat_Activity;
datname | pid | client_addr | client_port | backend_start | query_start | state
---------+-------+---------------+-------------+-------------------------------+-------------------------------+--------
birstdb | 10046 | | -1 | 2018-03-27 20:40:11.721804-05 | 2018-03-27 20:47:27.118434-05 | active
birstdb | 10082 | 192.168.1.187 | 55859 | 2018-03-27 20:43:55.301216-05 | 2018-03-27 20:46:07.190064-05 | idle

ps -fu armandp
UID PID PPID C STIME TTY TIME CMD
armandp 3264 3263 0 20:39:13 pts/2 0:00 tail -f /u1/sys_admin/dba/ingres2birst.fifo
armandp 3265 3263 0 20:39:13 pts/2 0:00 psql -U csidba -d birstdb -h 172.16.10.93

Give it about 10 min at most and bam out it goes

birstdb=# select datname, pid, client_addr, client_port, backend_start, query_start, state from pg_stat_Activity;
datname | pid | client_addr | client_port | backend_start | query_start | state
---------+-------+-------------+-------------+-------------------------------+-------------------------------+--------
birstdb | 10208 | | -1 | 2018-03-27 20:51:25.835382-05 | 2018-03-27 21:08:47.164249-05 | active

Although the above two processes are still out

I think the tcp keep alives might help but I am also thinking like a each min check maybe and if things got in the pipe well dump ‘em to Postgres. Something along these lines

Any ideas/suggestions you might have to improve this ? I am not saying it is perfect far from it, but I kinda took the model/idea from the Nagios named pipe only that one too runs at x seconds/minutes interval defined

Thank you both
— Armand