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RE: RE: Why is Oracle process using 25 MB of RAM when idle?

From: Stephane Faroult <>
Date: Mon, 17 Nov 2003 05:14:26 -0800
Message-ID: <>


  Seems a bit high to me as well. Concerning the PGA issue, what about running something like :

col name format A25

       round(min(s.value) / 1024) "MIN K",
       round(avg(s.value) / 1024) "AVG K",
       round(max(s.value) / 1024) "MAX K"
from v$statname n,
     v$sesstat s

where like 'session pga memory%'
  and n.statistic# = s.statistic#
group by

IMHO, the Oracle "insider view" will probably give you something more realistic. Now, concerning what HP-UX reports to you, I would certainly suspect the run-time linker. I guess that there are better specialists of HP-UX than myself (anybody qualifies :-)) on this list who know how to tell which dynamically loaded libraries are used by a currently running program ?


>----- ------- Original Message ------- -----
>From: "Daiminger, Helmut" <>
>To: Multiple recipients of list ORACLE-L
>Sent: Mon, 17 Nov 2003 03:59:26
>Hi Stephane,
>thanks for your reply.
>We are measuring the values by getting the OS
>process ID of a specific
>Oracle connection and then trach that process ID
>using glance (on HP-UX).
>Since the SGA is ab 1.5 GB, it is definitely not
>attached to the memory
>consumed by each process. I know that this is an
>issue on Solaris.
>We tried and used a whole bunch of different
>processes and they were all
>using 20-25 MB of RAM (doing nothing). This number
>seems just a little bit
>high to me...
>Example: If I have an SGA with 1 GB, 200 MB of
>pga-aggregate-target and 200
>users connecting to the datbase (although only
>about 10% of them are active
>at the same point in time).
>This would mean that my memory consumption is: 1 GB
>+ 200 MB + 200*25 MB =
>6.2 GB...
>-----Original Message-----
>Sent: Monday, November 17, 2003 10:30 AM
>To: Multiple recipients of list ORACLE-L
> I don't know how you are measuring your numbers,
>but beware that what the
>operating system reports is often somewhat
>misleading. Typically, shared
>memory is often 'attributed' to each and every
>process linked to it. When
>you think about it it makes sense, but at the same
>time it does mean that n
>processes will really use much less than n * the
>amount of memory reported
>as used by one process. This is true both of the
>'program' part of user
>memory (shared libraries) and of the 'data' part of
>it (SGA). When your
>process connects, it attaches the SGA and some
>shared libraries, and more
>shared libraries come into play as it starts doing
>something. You may have a
>better view of what is really used by your process
>by checking into
>V$SESSTAT, which holds a number of values about it.
>>----- ------- Original Message ------- -----
>>From: "Daiminger, Helmut"
>>To: Multiple recipients of list ORACLE-L
>>Sent: Sun, 16 Nov 2003 23:09:26
>>we are running 9.2 on HP-UX here.
>>We have pg_aggregate_target configured, but I
>>realized (in my opinion) very
>>high memory consumption of Oracle Unix processes.
>>a) How come that one Oracle Connection (i.e.
>>dedicated Unix process on HP)
>>is using up at least 22 MB of RAM? It is using 22
>>MB if the user is just
>>connected, not doing anything.
>>Any way I can modify this?
>>b) If the user is querying data and the like, the
>>memory consumption goes up
>>to 60 MB. How come?

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Author: Stephane Faroult

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Received on Mon Nov 17 2003 - 07:14:26 CST

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