Re: pg_stat_activity doubts

On 3/22/18 10:01 AM, Debraj Manna wrote:

> Thanks Ray .
>
> Any thoughts on my query #3?

I would do an strace on the pid to see what is underneath.  Might give a
clue where to look in the code.

>
> On Thu 22 Mar, 2018, 7:13 PM Ray Stell, <stellr(at)vt(dot)edu
> <mailto:stellr(at)vt(dot)edu>> wrote:
>
> On 3/22/18 8:45 AM, Debraj Manna wrote:
>
>> Hi
>>
>> Can someone resolve my below doubts about pg_stat_activity :-
>>
>> 1. Can someone let me know how pg_stat_activity is populated? If
>> I am executing a query like `Select * from pg_stat_activity`
>> does it produce the details from some snapshot maintained by
>> postgres or it checks the current connections open in
>> postgres to provide the details?
>> 2. Can some let me know what does the state IDLE denotes in the
>> row of pg_stat_activity? Is it like it checks all the open
>> connections to postgres and if the connection is not
>> executing any query then IDLE denotes the last query executed
>> by the connection?
>> 3. In the output of select * from pg_stat_activity I am seeing
>> rows with state IDLE and the query_start_date more than 2
>> days old? What does this signify ? Should I be worried about
>> this?
>> 4.
>>
>