We may face this problem when in our sharepoint publishing site, we may face the error.

刷新共享对象管理器缓存时发生意外错误。

System.InvalidOperationException:超时时间已到。超时时间已到，但是尚未从池中获取连接。出现这种情况可能是因为所有池连接均在使用，并且达到了最大池大小。

超时时间已到。超时时间已到，但是尚未从池中获取连接。出现这种情况可能是因为所有池连接均在使用，并且达到了最大池大小。   在 System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection)
   在 System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory)
   在 System.Data.SqlClient.SqlConnection.Open()
   在 Microsoft.Office.Server.Data.SqlSession.OpenConnection()
   在 Microsoft.Office.Server.Data.SqlSession.ExecuteReader(SqlCommand command, CommandBehavior behavior)
   在 Microsoft.Office.Server.Data.SqlSession.ExecuteReader(SqlCommand command)
   在 Microsoft.Office.Server.UserProfiles.DBHelper.RunSqlCommand(SqlCommand command)
   在 Microsoft.Office.Server.UserProfiles.UserProfile.RetrieveUser(String strAcct, Guid gAcct, Byte[] bSid, Nullable`1 recordId, Boolean doNotResolveToMasterAccount)
   在 Microsoft.Office.Server.UserProfiles.UserProfile..ctor(UserProfileManager objManager, String strAcct, Boolean doNotResolveToMasterAccount, Boolean forceUserIsSelf)
   在 Microsoft.Office.Server.UserProfiles.UserProfileManager.GetUserProfile(Boolean bCreateIfNotExist, Boolean bIsFirstAttempt)
   在 Microsoft.Office.Server.UserProfiles.UserProfileManager.GetUserProfile(Boolean bCreateIfNotExist)
   在 Microsoft.Office.Server.UserProfiles.ProfileLoader.EnsureUserProfile()
   在 Microsoft.Office.Server.UserProfiles.ProfileLoader.GetUserProfile()
   在 Microsoft.SharePoint.Portal.WebControls.PersonalPageCommon.OnInit(Page objPage)
   在 Microsoft.SharePoint.Portal.WebControls.PersonalAdminPage.OnInit(EventArgs e)
   在 System.Web.UI.Control.InitRecursive(Control namingContainer)
   在 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

Unlucky, although we close all sql connections in our code, we still can't solve this.

But it may another cause for it about uploading large file to sharepoint.

When we need to uplaod large file to sharepoint in windows 2008, we can infer this article below:

http://support.microsoft.com/kb/925083

We add

to "configuration" node to allow large file uploading.

Then we meet the problem. Clear it will solve it.

It is just a superficial reason for the error. There is also error in SharePoint SPP, but I haven't figured it out.

Any progress, I will update this.