pg.ddx.io  pgsql-performance@postgresql.org mailing list archive  
help / color / mirror / Atom feed
Postgress memory leak with JBoss3.2.6 and large DB
5+ messages / 4 participants
[nested] [flat]

* Postgress memory leak with JBoss3.2.6 and large DB
@ 2006-08-31 16:52  Indika Maligaspe <indika@rezgateway.com>
  0 siblings, 2 replies; 5+ messages in thread

From: Indika Maligaspe @ 2006-08-31 16:52 UTC (permalink / raw)
  To: pgsql-performance

Hey guys,

  We are running a Linux 2.4 enterprise edition box with 6GB of RAM,
Postgres 8.0.3. Our applications are running on JBoss 3.2.6. We are having a
Database of over 22GB in size.

The problem is when we are querying a specific set of table (which all
tables having over 100K  of rows), the Postgres user process takes over or
close 700MB of memory. This is just to return 3000 odd rows. Even though we
have lot of data we still do not have that much to eat up this much of
memory.

 

What I would like to know is, is there any setting in the Postgres or in
Linux that we can tune this with?

 

Our Postgres.conf file has the following settings, we have been playing
around wit this but still no success.

 

shared_buffers = 5000    

effective_cache_size = 10000     

work_mem =  2048                                

random_page_cost = 2   

 

A sample of the top command is given below.

 

12:38:05  up 136 days,  7:06, 10 users,  load average: 7.69, 4.83, 3.78

459 processes: 458 sleeping, 1 running, 0 zombie, 0 stopped

CPU states:  cpu    user    nice  system    irq  softirq  iowait    idle

           total    9.6%    0.0%    1.8%   0.0%     0.0%   88.3%    0.0%

           cpu00   11.3%    0.0%    0.3%   0.0%     0.1%   88.0%    0.0%

           cpu01    8.9%    0.0%    2.5%   0.0%     0.0%   88.4%    0.0%

           cpu02   14.1%    0.0%    2.9%   0.0%     0.0%   82.9%    0.0%

           cpu03    4.1%    0.0%    1.5%   0.1%     0.1%   93.8%    0.0%

Mem:  6153976k av, 6092084k used,   61892k free,       0k shrd,    6232k
buff

                   4769364k actv,  916224k in_d,  111336k in_c

Swap: 1052216k av,  761912k used,  290304k free                 3036700k
cached

 

  PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME CPU COMMAND

19736 postgres  15   0  508M 448M 42840 D     0.9  7.4   0:22   0 postmaster

19740 postgres  15   0  507M 441M 41428 D     0.8  7.3   0:21   0 postmaster

19779 postgres  15   0  508M 472M 42828 D     0.8  7.8   0:21   0 postmaster

19789 postgres  15   0  508M 477M 42412 D     0.6  7.9   0:21   0 postmaster

19738 postgres  15   0  507M 438M 41852 D     0.4  7.3   0:21   0 postmaster

14647 postgres  15   0 63948  56M 44236 D     0.1  0.9   0:41   3 postmaster

 

As you can see the postmaster users are taking way over the memory that
should be taken.

 

If any of you can give us some pointers we would really appreciate that and
thanks in advance.

 

Regards

Indika.

^ permalink  raw  reply  [nested|flat] 5+ messages in thread

* Re: Postgress memory leak with JBoss3.2.6 and large DB
@ 2006-08-31 17:54  Tom Lane <tgl@sss.pgh.pa.us>
  parent: Indika Maligaspe <indika@rezgateway.com>
  1 sibling, 1 reply; 5+ messages in thread

From: Tom Lane @ 2006-08-31 17:54 UTC (permalink / raw)
  To: Indika Maligaspe <indika@rezgateway.com>; +Cc: pgsql-performance

"Indika Maligaspe" <indika@rezgateway.com> writes:
> The problem is when we are querying a specific set of table (which all
> tables having over 100K  of rows), the Postgres user process takes over or
> close 700MB of memory. This is just to return 3000 odd rows. Even though we
> have lot of data we still do not have that much to eat up this much of
> memory.

Playing with server-side settings won't have the slightest effect on a
client-side problem.  I'd suggest asking about this on the pgsql-jdbc
list; they are more likely to have useful suggestions than backend
hackers will.

			regards, tom lane



^ permalink  raw  reply  [nested|flat] 5+ messages in thread

* Re: Postgress memory leak with JBoss3.2.6 and large DB
@ 2006-08-31 18:11  Dave Cramer <pg@fastcrypt.com>
  parent: Tom Lane <tgl@sss.pgh.pa.us>
  0 siblings, 0 replies; 5+ messages in thread

From: Dave Cramer @ 2006-08-31 18:11 UTC (permalink / raw)
  To: Tom Lane <tgl@sss.pgh.pa.us>; +Cc: Indika Maligaspe <indika@rezgateway.com>; pgsql-performance


On 31-Aug-06, at 1:54 PM, Tom Lane wrote:

> "Indika Maligaspe" <indika@rezgateway.com> writes:
>> The problem is when we are querying a specific set of table (which  
>> all
>> tables having over 100K  of rows), the Postgres user process takes  
>> over or
>> close 700MB of memory. This is just to return 3000 odd rows. Even  
>> though we
>> have lot of data we still do not have that much to eat up this  
>> much of
>> memory.
>
> Playing with server-side settings won't have the slightest effect on a
> client-side problem.  I'd suggest asking about this on the pgsql-jdbc
> list; they are more likely to have useful suggestions than backend
> hackers will.

What is the query here. I doubt this is a client side problem, as we  
are still looking at the server side processes, not the java  
processes here.

Also your memory settings are *way* too low
Dave
>
> 			regards, tom lane
>
> ---------------------------(end of  
> broadcast)---------------------------
> TIP 1: if posting/reading through Usenet, please send an appropriate
>        subscribe-nomail command to majordomo@postgresql.org so that  
> your
>        message can get through to the mailing list cleanly
>




^ permalink  raw  reply  [nested|flat] 5+ messages in thread

* Re: Postgress memory leak with JBoss3.2.6 and large DB
@ 2006-09-04 03:53  Mark Kirkwood <markir@paradise.net.nz>
  parent: Indika Maligaspe <indika@rezgateway.com>
  1 sibling, 1 reply; 5+ messages in thread

From: Mark Kirkwood @ 2006-09-04 03:53 UTC (permalink / raw)
  To: pgsql-performance

Indika Maligaspe wrote:
> Hey guys,
> 
>   We are running a Linux 2.4 enterprise edition box with 6GB of RAM, 
> **Postgres 8.0.3**. (snippage)
> 

You might want to consider upgrading to 8.0.8 (see below), and seeing if
the problem still persists.


> As you can see the postmaster users are taking way over the memory that 
> should be taken.
>   
> 
> If any of you can give us some pointers we would really appreciate that 
> and thanks in advance.
> 

I notice that there are a number of fixes for memory leaks since 8.0.3 -
8.0.4 and 8.0.8 is where I see 'em specifically (reading release notes
for 8.0.8). So you may be experiencing an issue that is fixed in the
current 8.0 releases! I recommend upgrading to 8.0.8.

You didn't say what your HW was, but if you are on a 32-bit platform,
then a 2.4 kernel when you have >2G ram may leak noticeable amounts of
memory itself...

Cheers

Mark




^ permalink  raw  reply  [nested|flat] 5+ messages in thread

* Re: Postgress memory leak with JBoss3.2.6 and large DB
@ 2006-09-05 04:02  Indika Maligaspe <indika@rezgateway.com>
  parent: Mark Kirkwood <markir@paradise.net.nz>
  0 siblings, 0 replies; 5+ messages in thread

From: Indika Maligaspe @ 2006-09-05 04:02 UTC (permalink / raw)
  To: 'Mark Kirkwood' <markir@paradise.net.nz>; pgsql-performance

Hi Guys,
	We found the issue regarding our memory leak. It was the query. It
seams were using functions with fetch cursors on large data sets and the
cursors were not getting closed properly. Hence the memory was building up.
So I guess this was an application error. In fact we bought the Query memory
from 1.4 GB to 2 MB.........

Thanks for all the help guys. Because by reading all your comments I was
able to understand a lot about Postgres memory settings. 


K.Indika Maligaspe

-----Original Message-----
From: pgsql-performance-owner@postgresql.org
[mailto:pgsql-performance-owner@postgresql.org] On Behalf Of Mark Kirkwood
Sent: Monday, September 04, 2006 9:23 AM
To: pgsql-performance@postgresql.org
Subject: Re: [PERFORM] Postgress memory leak with JBoss3.2.6 and large DB

Indika Maligaspe wrote:
> Hey guys,
> 
>   We are running a Linux 2.4 enterprise edition box with 6GB of RAM, 
> **Postgres 8.0.3**. (snippage)
> 

You might want to consider upgrading to 8.0.8 (see below), and seeing if
the problem still persists.


> As you can see the postmaster users are taking way over the memory that 
> should be taken.
>   
> 
> If any of you can give us some pointers we would really appreciate that 
> and thanks in advance.
> 

I notice that there are a number of fixes for memory leaks since 8.0.3 -
8.0.4 and 8.0.8 is where I see 'em specifically (reading release notes
for 8.0.8). So you may be experiencing an issue that is fixed in the
current 8.0 releases! I recommend upgrading to 8.0.8.

You didn't say what your HW was, but if you are on a 32-bit platform,
then a 2.4 kernel when you have >2G ram may leak noticeable amounts of
memory itself...

Cheers

Mark


---------------------------(end of broadcast)---------------------------
TIP 4: Have you searched our list archives?

               http://archives.postgresql.org




^ permalink  raw  reply  [nested|flat] 5+ messages in thread


end of thread, other threads:[~2006-09-05 04:02 UTC | newest]

Thread overview: 5+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2006-08-31 16:52 Postgress memory leak with JBoss3.2.6 and large DB Indika Maligaspe <indika@rezgateway.com>
2006-08-31 17:54 ` Tom Lane <tgl@sss.pgh.pa.us>
2006-08-31 18:11   ` Dave Cramer <pg@fastcrypt.com>
2006-09-04 03:53 ` Mark Kirkwood <markir@paradise.net.nz>
2006-09-05 04:02   ` Indika Maligaspe <indika@rezgateway.com>

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox