Object Cache Accounts

Many administrators when they first configure SharePoint 2010 and hit a Web Application for the first time are likely to see a recurring event in the event log stating that the object cache has not been configured correctly. The specific error is as follows:

Object Cache: The super user account utilized by the cache is not configured. This can increase the number of cache misses, which causes the page requests to consume unneccesary system resources.

This is essentially telling you that you have missed a manual configuration step in which you need to run some PowerShell to set two accounts for SharePoint to use to access the object cache:

function Set-WebAppUserPolicy($webApp, $userName, $userDisplayName, $perm) {
    [Microsoft.SharePoint.Administration.SPPolicyCollection]$policies = $webApp.Policies
    [Microsoft.SharePoint.Administration.SPPolicy]$policy = $policies.Add($userName, $userDisplayName)
    [Microsoft.SharePoint.Administration.SPPolicyRole]$policyRole = $webApp.PolicyRoles | where {$_.Name -eq $perm}
    if ($policyRole -ne $null) {
        $policy.PolicyRoleBindings.Add($policyRole)
    }
    $webApp.Update()
}
$webApp = Get-SPWebApplication "http://content"
$portalSuperUserAccount = Get-Credential "localdev\SPSuperUser"
$webApp.Properties["portalsuperuseraccount"] = $portalSuperUserAccount.UserName
Set-WebAppUserPolicy $webApp $portalSuperUserAccount.UserName $portalSuperUserAccount.UserName "Full Control"

$portalSuperReaderAccount = Get-Credential "localdev\SPSuperReader"
$webApp.Properties["portalsuperreaderaccount"] = $portalSuperReaderAccount.UserName
Set-WebAppUserPolicy $webApp $portalSuperReaderAccount.UserName $portalSuperReaderAccount.UserName "Full Read"

Make sure that you do not use the same account for both the super user and super reader. (And of course make sure you change the URL and account names to match your environment).

For more information about these settings see the following TechNet article: http://technet.microsoft.com/en-us/library/ff758656.aspx