Oracle 10g is installed on the Windows 2003 32-bit operating system, the number of connections to 120 can not be connected, reported ora12518____oracle

Server IBM Xserver, RAM: 4G
The main parameters for Oracle database configuration are as follows:
Processes integer 800
Sessions integer 885
Pga_aggregate_target Big Integer 350M
Sga_max_size Big Integer 1256M
Sga_target Big Integer 1152M
Shared_pool_size Big Integer 400M
Large_pool_size Big Integer 16M

The number of connections to the database configuration is 800, but now when the number of Oracle connections reaches 250, the other clients will no longer be able to connect to the Oracle server and make a mistake: Ora-12518:tns: The listener cannot distribute the client;
But has been connected to the application of the database can also be normal application, that is not connected to the other is not even on the, unless the existing connection has exited, the other can be linked, that is, the total number of connected to 250;
Internet search: Said is in the Listener.ora can join a line: Direct_handoff_ttc_<listener Name>=off, but still not;
During this time, we tried to
Pga_aggregate_target changed to 200 or 500, the result is the same;
Sga_target changed to 800m, the result of the database will not start, the hint that should not be less than 1024m;

Later found that there may be an Oracle 10g for Win32 a bug, the internet has been patched, after the release of the patch is: 10.2.0.3, but also suspected that Windows 2003 TCP connections are not enough, the internet to say that seems to have this problem, under a 2003 patch, The TCP connection number is expanded to 1000, the result can reach 350 concurrent connections, but no more is not connected;
It is not clear what parameter configuration is not appropriate, (whether it is oracle10g, or Windows 2003), which can not be connected to the maximum number of connections that have actually been set by Oracle.

Later, we suspected that the Windows 2003 32-bit problem, so we installed a 64-bit Windows 2003, the same version of Oracle 10g, installed after the connection number process parameters configured to 800, and then do the connection test, has been able to have 800 sessions to join up, so far, can be summed up the crux of the problem is that we installed this Windows 2003 server (31-bit)Operating System, there is a problem installing Oracle 10g (10.2.0.1-10.2.0.3), the number of connections cannot be as large as the system configuration, and 64-bit substitution can be used. But I was wondering why the Windows 2003 server (31-bit) operating system +oracle the number of 10g database connections would be limited, and if there was any way to modify the 2003 configuration or Oracle 10g configuration, you couldSolveOff this problem,

Solution II,

Solution:

First, modify Oracle Parameters

1, the original parameters indicated: red for the original parameters, blue for the increased parameters

#pga_aggregate_target =67108864

#processes =500

#sessions =555

# Pga_aggregate_target This parameter is to enlarge the number of concurrent connections to occupy memory size.

# You can resize this parameter to zoom in or out, while affecting the concurrent quantity.

# formula: approx = *4m according to concurrent quantity

pga_aggregate_target=720m

# processes, Sessions is to expand the number of concurrent connections, is used at the same time.

# formula: Sessions = Processes *1.1 +5

processes=600

sessions=665

2, in the listening parameter file Listener.ora file to add parameters

Direct_handoff_ttc_listener = Off

3, restart the database service.

Ii. 1, modify Boot.ini files in Windows system

/3gb/pae

Note: Modify the Boot.ini files in the operating system to enable Oracle to use more memory space.

2, modify the user Group Policy locked memory page size permissions.

Parameter modification complete problem solved.

3, restart the computer.