Thread: Monitoring DB activity PosgreSQL 7.3.2

Monitoring DB activity PosgreSQL 7.3.2

From
Andre Truter
Date:
Hi,

I have PostgreSQL 7.3.2 server running.
I could normally view the sessions by doing
'ps auxww | grep ^postgres' like the documentation states.

But, recently it is not showing me expected output anymore.

THis is what I get:
postgres  1661  0.0  0.0  9132  176 ?        S    Jul18   0:00
[postmaster]
postgres  1665  0.0  0.0 10124   56 ?        S    Jul18   0:00
[postmaster]
postgres  1666  0.0  0.0  9204  236 ?        S    Jul18   0:00
[postmaster]
postgres  1848  0.0  0.0  9944    0 ?        SW   Jul27   0:00
[postmaster]
postgres  4082  0.0  0.0  9844    0 ?        SW   Jul27   0:00
[postmaster]
postgres  4083  0.0  0.0 10512    0 ?        SW   Jul27   0:00
[postmaster]
postgres  4084  0.0  0.0 10604    0 ?        SW   Jul27   0:00
[postmaster]
postgres  5089  0.0  0.0  9908    4 ?        S    Jul27   0:00
[postmaster]
postgres  5963  0.0  0.0  9908    0 ?        SW   Jul27   0:00
[postmaster]
postgres  5984  0.0  0.0  9844    0 ?        SW   Jul27   0:00
[postmaster]
postgres 18014  0.0  0.8 11316 4348 ?        S    09:28   0:01
[postmaster]
postgres 18431  0.0  0.8 11168 4544 ?        S    10:02   0:00
[postmaster]

Is there a different way of seeing the user sessions?


I thought that my documentation was out of date, so I tried the
PostgreSQL site, but that seems to be out of order.
http://www.postgresql.org/ gives me the Apache test page.

--
Andre Truter
Software Engineer
Registered Linux user #185282
ICQ #40935899  AIM: trusoftzaf
http://www.trusoft.za.net

<------------------------------------------------->
< The box said: Requires Windows 95 or better...  >
< So I installed Linux                            >
<------------------------------------------------->


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Re: Monitoring DB activity PosgreSQL 7.3.2

From
Andre Truter
Date:
On Mon, 2003-07-28 at 17:27, Alvaro Herrera wrote:

> The processes with the W status are swapped out.  In some Linux versions
> and maybe some other platforms, swapped out processes have the
> /proc/<pid>/cmdline file truncated, so ps uses the /proc/<pid>/exe
> symlink instead, which does know what executable file the process is
> running ("postmaster"), but not the nice status line that Postgres sets.
>
> Well, whether you understand or not what I just said, truth is the
> mechanism for showing process status in ps is not bulletproof, and this
> is one example where it fails :-(

Yes, I am beginning to suspect 'ps', as it is currently showing about
half of all processes to be swapped out, even though top shows them to
be very active.

Very weird....
--
Andre Truter
Software Engineer
Registered Linux user #185282
ICQ #40935899  AIM: trusoftzaf
http://www.trusoft.za.net

<------------------------------------------------->
< The box said: Requires Windows 95 or better...  >
< So I installed Linux                            >
<------------------------------------------------->


Disclaimer and Confidentiality Warning

This message is intended for the addressee only. If you are not the intended recipient of this message, you are
notifiedthat any distribution, use of or copying of this communication is strictly prohibited. If you have received the
communicationin error, please notify the sender immediately. The views and opinions expressed in this message are those
ofthe individual sender of this message and do not necessarily represent the views and opinions of ATIO. Consequently,
ATIOdoes not accept responsibility for such views and opinions and this message should not be read as representing the
viewsand opinions of ATIO without subsequent written confirmation. Each page attached hereto must also be read in
conjunctionwith this disclaimer. 


Re: Monitoring DB activity PosgreSQL 7.3.2

From
Alvaro Herrera
Date:
On Mon, Jul 28, 2003 at 12:36:29PM +0200, Andre Truter wrote:

> I have PostgreSQL 7.3.2 server running.
> I could normally view the sessions by doing
> 'ps auxww | grep ^postgres' like the documentation states.
>
> But, recently it is not showing me expected output anymore.
>
> THis is what I get:
> postgres  1661  0.0  0.0  9132  176 ?        S    Jul18   0:00 [postmaster]
> postgres  1848  0.0  0.0  9944    0 ?        SW   Jul27   0:00 [postmaster]

The processes with the W status are swapped out.  In some Linux versions
and maybe some other platforms, swapped out processes have the
/proc/<pid>/cmdline file truncated, so ps uses the /proc/<pid>/exe
symlink instead, which does know what executable file the process is
running ("postmaster"), but not the nice status line that Postgres sets.

Well, whether you understand or not what I just said, truth is the
mechanism for showing process status in ps is not bulletproof, and this
is one example where it fails :-(

--
Alvaro Herrera (<alvherre[a]dcc.uchile.cl>)
"A wizard is never late, Frodo Baggins, nor is he early.
He arrives precisely when he means to."  (Gandalf, en LoTR FoTR)