DOCUMENT:Q229814  20-NOV-2000  [iis]
TITLE   :Configuring IIS to Handle Heavy Usage
PRODUCT :Internet Information Server
PROD/VER::4.0,5.0
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Internet Information Server versions 4.0, 5.0 
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SYMPTOMS
========

A computer running Microsoft Internet Information Server (IIS) 4.0 may stop
responding to client requests, even though the server appears to be stable and
healthy. This situation usually arises from a heavy load; however, IIS does not
consume large amounts of CPU or memory resources. This behavior may occur on a
per-network interface card, IP address, or TCP port basis. A Network Monitor
trace will indicate that the server is immediately resetting TCP connections,
indicating that the physical, network, and transport layers are functioning at
full capacity.

CAUSE
=====

The problem occurs because of a lack of resources at the application layer to
handle the requests.

RESOLUTION
==========

Set the following metabase parameters:

    - ServerListenBacklog

 - MaxEndPointConnections

Increasing these values will result in an increase in handle count and memory
usage. The values need to be tuned to achieve a balance between load handling
capacity and memory usage.

MORE INFORMATION
================

The ServerListenBacklog property specifies the number of outstanding sockets
that can be queued. This value is based on the operating system parameter and
the server size specified in the ServerSize property.

   ServerListenBacklog
   Range: 0 (unlimited)
   Default: 40

Use Adsutil.vbs to change the value.

The Windows Script Host must be installed on the server to run this Visual Basic
script:

   cscript c:\winnt\system32\inetsrv\adminsamples\adsutil.vbs
   SET w3svc/1/ServerListenBacklog 500

The MaxEndpointConnections property specifies the maximum number of listen
sockets that will be aggregated on a network endpoint. For example, if this
value is set to 15, a maximum of 15 total connections can be made to a single
port, even if more than one domain is bound to the port.

   MaxEndPointConnections
   Range: 0 (unlimited)
   Default: -1 (unlimited)

Use Adsutil.vbs to change the value.

REFERENCES
==========

Online Product Documentation

Additional query words: Overload time_wait IIS TCP RESETS

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Keywords          :  
Technology        : kbiisSearch kbiis500 kbiis400
Version           : :4.0,5.0
Issue type        : kbprb

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