PRB: The server is too busy to handle your request

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This article applies to:

  • WebMarshal 6.X and 7.X


  • WebMarshal is not servicing all of the users connecting to the WMProxy service 
  • Error message returned to the browser: The server is too busy to handle your request


The WebMarshal Proxy service allows a limited number of connections by default, to limit the load placed on the service. 

  • In versions 6.9.2 and below, the default maximum value is 1000.
  • In versions 6.9.5 and 6.9.6, the default maximum value is 4000. See the warning about 64 bit systems, below.
  • In version 6.10 and above, the default values depend on the bitness of the operating system. For a 32 bit system the default is 4000. For a 64 bit system the default is 6000.
    • On upgrade to 6.9.5 and above, if the default value of 1000 was in use and never customized, the new default value will be applied.


You can increase or decrease the WebMarshal connection limit as needed, using the WebMarshal Server Tool (or directly editing files in earlier versions). See Instructions below.

However, you must ensure that your system has adequate resources. Read the version specific information first.

The number of connections is NOT equivalent to the number of users being serviced. Connections are data channels opened by the browser to the WebMarshal Proxy service in relation to number of windows or "tabs" opened by the user in their browser. Each tab will generate 2-3 connections and since most browser only have one active tab at any time there is usually only a small number of connections open from that browser. However if all tabs are refreshed then the number of connections will increase proportional to the number of tabs.

WebMarshal 7.X

These versions of WebMarshal provide full 64 bit architecture. Ensure that your system has adequate resources for the Proxy, Engine, and 64 bit operating system.

WebMarshal 6.10 (and above):

These versions of WebMarshal install a native 64 bit version of the Proxy on 64 bit systems. This enhancement removes some limitations on total connections available. However, note that the default maximum of 6000 connections will consume between 1 and 2 GB of memory for thread stack space alone if the maximum connections are actually in use. Ensure that your system has adequate resources.

WebMarshal 6.9:

For these systems, 3000 connections is the practical maximum for most 64 bit installations. Connections consume more memory on 64 bit systems.

  • You may need to reduce the setting because the default for version 6.9.6 is 4000 connections.

Increase the number of connections incrementally (for instance 500 connections at a time) and evaluate server load after each change, particularly during peak browsing periods, to ensure the processing node can handle the load. If the number of connections required exceeds the node's ability to support the processing load, then additional node hardware should be installed.

4000 connections, the default maximum for WebMarshal 6.9.5 and above, would consume 1 GB of memory (on 32 bit systems) or 2 GB of memory (on 64 bit systems) for thread stack space alone (only if all 4000 are actually in use).


 If you have more than one processing server, you must make the changes on each server.

  • In version 6.5.5 and above, use the WebMarshal Server Tool > Advanced tab, and change the value of  the field Number of Threads.
  •  In version 6.0.3 and above, you can add an entry in the WebMarshal Proxy Configuration file (WMProxy.config.xml) as follows, inserting the appropriate number:

            <ProxySettings numThreads="1500" />

To apply the change, restart the Proxy service. If you use the Server Tool, you will be prompted.


  • For general information about editing XML settings files, see article Q12705.
  • The file WMProxy.config.xml is located on the processing server. If you have more than one processing server, you must make the changes on each server.
  • Back up configuration before making changes.
  • The file WMProxy.config.xml normally contains additional settings. The ProxySettings node can have multiple attributes. This node must only occur once.
  • Only add (or edit) the specific attribute numThreads.
  • The maximum value allowed is:
    • Version 6.9: 8000
    • Version 6.10 and above: 6000 (32 bit) or 9000 (64 bit)

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