Periodic Restart Settings for Application Pool Recycling <periodicRestart>


The <periodicRestart> element contains configuration settings that allow you to control when an application pool is recycled. You can specify that Internet Information Services (IIS) 7 recycle the application pool after a time interval (in minutes) or at a specific time each day. You can also configure IIS to base the recycle on the amount of virtual memory or physical memory that the worker process in the application pool is using or configure IIS to recycle the application pool after the worker process has processed a specific number of requests.


Version Notes
IIS 7.5 The <periodicRestart> element was not modified in IIS 7.5.
IIS 7.0 The <periodicRestart> element was introduced in IIS 7.0.
IIS 6.0 The <periodicRestart> element replaces portions of the IIS 6.0 IIsApplicationPools metabase property.


The <applicationPools> collection is included in the default installation of IIS 7.

How To

How to set up periodic recycling for an application pool

  1. Open Internet Information Services (IIS) Manager:
    • If you are using Windows Server 2008 or Windows Server 2008 R2:
      • On the taskbar, click Start, point to Administrative Tools, and then click Internet Information Services (IIS) Manager.
    • If you are using Windows Vista or Windows 7:
      • On the taskbar, click Start, and then click Control Panel.
      • Double-click Administrative Tools, and then double-click Internet Information Services (IIS) Manager.
  2. In the Connections pane, expand the server name, and then click Application Pools.
  3. In the Application Pools pane, select the application pool you want edit.
  4. In the Actions pane, click Recycling...

  5. On the Recycling Conditions page of the Edit Application Pool Recycling Settings Wizard, select at least one of the options in the Fixed Intervals section, type values into the appropriate text boxes, and then click Next.

  6. (Optional) On the Recycling Events to Log page of the Edit Application Pool Recycling Settings Wizard, select the configurable recycling events and run-time recycling events that you want IIS to send to the event log when they occur, and then click Finish.

    Note: By default, IIS sends the Regular time intervals, Virtual memory usage, and Private memory usage configurable recycling events to the event log. The other configurable recycling events are available for logging only if you have enabled the logging event on the Recycling Conditions page.


The <periodicRestart>element is configurable at the server level in the ApplicationHost.config file.


Attribute Description
memory Optional uint attribute.

Specifies the amount of virtual memory (in kilobytes) that a worker process can use before the worker process is recycled. The maximum value supported for this property is 4,294,967 KB.

The default value is 0, which disables the attribute.
privateMemory Optional uint attribute.

Specifies the amount of private memory (in kilobytes) that a worker process can use before the worker process recycles. The maximum value supported for this property is 4,294,967 KB.

The default value is 0, which disables the attribute.
requests Optional uint attribute.

Specifies that the worker process should be recycled after it processes a specific number of requests.

The default value is 0, which disables the attribute.
time Optional timeSpan attribute.

Specifies that the worker process should be recycled after a specified amount of time has elapsed.

The default value is 29:00:00 (29 hours).

Child Elements

Element Description
schedule Optional element.

Specifies the scheduling of periodic restarts of application pools.

Configuration Sample

The following configuration sample uses the application pool <add> element to create a new application pool named Contoso. The <recycling> element configures logging for application pool restarts, the <periodicRestart> element configures when the application pool restarts, and the <processModel> element configures the shutdownTimeLimit and startupTimeLimit attributes for shutting down and starting the worker processes in the application pool for 30 seconds each. If these time limits are exceeded, IIS terminates the worker process.

<add name="Contoso">
   <recycling logEventOnRecycle="Schedule">
            <clear />
            <add value="03:00:00" />
   <processModel identityType="NetworkService" shutdownTimeLimit="00:00:30" startupTimeLimit="00:00:30" />

Sample Code

The following code examples add an application pool named Contoso to your IIS 7 server, then set the application pool to daily recycle at 3:00 A.M.


appcmd.exe set config -section:system.applicationHost/applicationPools /+"[name='Contoso']" /commit:apphost

appcmd.exe set config -section:system.applicationHost/applicationPools /+"[name='Contoso'].recycling.periodicRestart.schedule.[value='03:00:00']" /commit:apphost

You can also use the following syntax:

appcmd.exe add apppool /name:"Contoso"

appcmd.exe set config -section:system.applicationHost/applicationPools /+"[name='Contoso'].recycling.periodicRestart.schedule.[value='03:00:00']" /commit:apphost

Note: You must be sure to set the commit parameter to apphost when you use AppCmd.exe to configure these settings. This commits the configuration settings to the appropriate location section in the ApplicationHost.config file.


using System;
using System.Text;
using Microsoft.Web.Administration;

internal static class Sample
   private static void Main()
      using (ServerManager serverManager = new ServerManager())
         Configuration config = serverManager.GetApplicationHostConfiguration();
         ConfigurationSection applicationPoolsSection = config.GetSection("system.applicationHost/applicationPools");
         ConfigurationElementCollection applicationPoolsCollection = applicationPoolsSection.GetCollection();
         ConfigurationElement addElement = applicationPoolsCollection.CreateElement("add");
         addElement["name"] = @"Contoso";
         ConfigurationElement recyclingElement = addElement.GetChildElement("recycling");
         ConfigurationElement periodicRestartElement = recyclingElement.GetChildElement("periodicRestart");
         ConfigurationElementCollection scheduleCollection = periodicRestartElement.GetCollection("schedule");
         ConfigurationElement addElement1 = scheduleCollection.CreateElement("add");
         addElement1["value"] = TimeSpan.Parse("03:00:00");


Imports System
Imports System.Text
Imports Microsoft.Web.Administration

Module Sample
   Sub Main()
      Dim serverManager As ServerManager = New ServerManager
      Dim config As Configuration = serverManager.GetApplicationHostConfiguration
      Dim applicationPoolsSection As ConfigurationSection = config.GetSection("system.applicationHost/applicationPools")
      Dim applicationPoolsCollection As ConfigurationElementCollection = applicationPoolsSection.GetCollection
      Dim addElement As ConfigurationElement = applicationPoolsCollection.CreateElement("add")
      addElement("name") = "Contoso"
      Dim recyclingElement As ConfigurationElement = addElement.GetChildElement("recycling")
      Dim periodicRestartElement As ConfigurationElement = recyclingElement.GetChildElement("periodicRestart")
      Dim scheduleCollection As ConfigurationElementCollection = periodicRestartElement.GetCollection("schedule")
      Dim addElement1 As ConfigurationElement = scheduleCollection.CreateElement("add")
      addElement1("value") = TimeSpan.Parse("03:00:00")
   End Sub
End Module


var adminManager = new ActiveXObject('Microsoft.ApplicationHost.WritableAdminManager');
adminManager.CommitPath = "MACHINE/WEBROOT/APPHOST";
var applicationPoolsSection = adminManager.GetAdminSection("system.applicationHost/applicationPools", "MACHINE/WEBROOT/APPHOST");
var applicationPoolsCollection = applicationPoolsSection.Collection;

var addElement = applicationPoolsCollection.CreateNewElement("add");
addElement.Properties.Item("name").Value = "Contoso";
var recyclingElement = addElement.ChildElements.Item("recycling");
var periodicRestartElement = recyclingElement.ChildElements.Item("periodicRestart");
var scheduleCollection = periodicRestartElement.ChildElements.Item("schedule").Collection;
var addElement1 = scheduleCollection.CreateNewElement("add");
addElement1.Properties.Item("value").Value = "03:00:00";



Set adminManager = createObject("Microsoft.ApplicationHost.WritableAdminManager")
adminManager.CommitPath = "MACHINE/WEBROOT/APPHOST"
Set applicationPoolsSection = adminManager.GetAdminSection("system.applicationHost/applicationPools", "MACHINE/WEBROOT/APPHOST")
Set applicationPoolsCollection = applicationPoolsSection.Collection

Set addElement = applicationPoolsCollection.CreateNewElement("add")
addElement.Properties.Item("name").Value = "Contoso"
Set recyclingElement = addElement.ChildElements.Item("recycling")
Set periodicRestartElement = recyclingElement.ChildElements.Item("periodicRestart")
Set scheduleCollection = periodicRestartElement.ChildElements.Item("schedule").Collection
Set addElement1 = scheduleCollection.CreateNewElement("add")
addElement1.Properties.Item("value").Value = "03:00:00"

Deprecated Elements