Re: 8.2.3: Server crashes on Windows using Eclipse/Junit - Mailing list pgsql-general

"Trevor Talbot" wrote:

>I wrote:
>
>[ desktop heap usage ]
>
>> It could be that there's a significant difference between XP and 2003
>> in how that's handled though.  I do have an XP SP2 machine here with
>> 512MB RAM, and I'll try tests on it as soon as I can free up what it's
>> currently occupied with.
>
>...yep, under XP I'm using about 3.1KB of the service heap per
>connection, which tears through it quite a bit faster.  Now to figure
>out exactly where it's coming from...

I can confirm this here (WinXP SP2).

I have restored the original postgresql.conf file that was created when the
cluster was initialized with Postgres 8.2.4-1 (the installed version now is
8.2.5-1). The only other change to this installation is that I have moved the
WAL directory pg_xlog to another drive using a junction link.

Here are my numbers from SysInternals System Information program:
Pages Limit:    364544KB  [356MB]
Nonpaged Limit: 262144KB  [256MB]
These limits are never reached.

Using the Desktop Heap Monitor every new connection consumes 3232 bytes of the
total 512KB heap.

>It could be that there's a significant difference between XP and 2003
>in how that's handled though.  I do have an XP SP2 machine here with
>512MB RAM, and I'll try tests on it as soon as I can free up what it's
>currently occupied with.

Yeah, Win2003 behaves differently accoriding to this source:
<http://blogs.msdn.com/ntdebugging/archive/2007/01/04/desktop-heap-overview.aspx>

<quote>
Session paged pool allows session specific paged pool allocations.  Windows XP
uses regular paged pool, since the number of remote desktop connections is
limited.  On the other hand, Windows Server 2003 makes allocations from
session paged pool instead of regular paged pool if Terminal Services
(application server mode) is installed.
</quote>

After increasing the session heap size in the registry from 512KB to 1024KB
the no. of connections was roughly doubled. So this might be a solution for
people running out of Desktop heap.

Alter the value of the following key
<HKLM\System\CurrentControlSet\Control\Session Manager\SubSystems\Windows>

The numeric values following "SharedSection=" control the heap management:
On WinXP these are the default values: "SharedSection=1024,3072,512"
Altering this to "SharedSection=1024,3072,1024" will increase the heap for all
non-interactive window stations to 1024KB.

Rainer