When selecting the Performance tab in VirtualCentre and selecting any period of longer than a day under Change Chart Options the graph is empty with the message "Performance data is currently not available for this entity".

Possible Resolutions:

1) VirtualCenter 1.X to 2.0 SQL Upgrade
A VirtualCenter 2.0 Server (using an MS SQL Server database) that has been upgraded from VirtualCenter 1.x may not display performance data in the VI Client. This problem does not affect fresh installations of VirtualCenter 2.0, nor any upgrade or fresh installation that uses an Oracle database.

Performance Data Is Not Displayed in VI Client Connected to VirtualCenter 2.0 Server after an Upgrade
http://kb.vmware.com/kb/6579181

2) Time Synchronisation between VirtualCenter and ESX hosts
If time synchronisation is not consistent between the VirtualCenter Server and the ESX hosts this message may be seen.

If time has been changed on an ESX host the following command may need to be run to start showing performance data straight away:

service mgmt-vmware restart

3) SQLSERVERAGENT Service not running on MS SQL Server
If the SQLSERVERAGENT is not running the following jobs are not run to generate stats:

- Past Day stats rollup
- Past Week stats rollup
- Past Month stats rollup

Start the SQLSERVERAGENT service and check the status of these jobs in SQL Enterprise Manager:

- <server> | Management | SQL Server Agent | Jobs

It will typically take an hour or two to generate these stats once the service is started.

If the jobs are missing from SQL Server Agent | Jobs in SQL Management Studio they can be recreated:

Repairing VirtualCenter 2.5 Server SQL Agent "Stats Rollup" Jobs
http://kb.vmware.com/kb/1004382

4) SQL Server 2005 Express Edition
This SQL vesion does not have a SQL Server Agent, so the stats rollup jobs will not be run.

Feature Comparison of MSDE and SQL Server 2005 Express
http://www.microsoft.com/technet/prodtechnol/sql/2005/msde2sqlexpress.mspx#EKE

SQL Server 2005 Features Comparison
http://www.microsoft.com/sql/prodinfo/features/compare-features.mspx

5) VirtualCenter Management Server Configuration
The level of statistics recorded is set in VirtualCenter:

- Select Administration | VirtualCenter Management Server Configuration | Statistics
- Ensure the Interval Durations are checked

6) Repair VirtualCenter
From the VitrualCenter server:

- Select Start | Control Panel | Add/Remove Programs
- Select VMware VitrualCenter Server
- Click Change
- Click Next on the VMware VirtualCenter Server dialogue
- Select the Repair radio button and click Next
- Click Next to use an existing database server
- Enter the database credentials and click Next
- Click No to the reinitialize the VirtualCenter repository dialogue
- Click OK to SQL Server Agent warning
- Select the use existing license server and click Next
- Click Next to accept license server and version
- Click Next to accept ports
- Click Next to accept Tomcat ports
- Click Install

7) Performance statistics rollup failure due to arithmetic overflow errors
VirtualCenter Server 2.5 uses the SQL Server Agent to periodically execute procedures that roll up collected performance statistic data. In some instances, data processed may exceed the datatype allocated and an arithmetic overflow error is seen in the SQL Server Agent job history.

The error message appears similar to the following:

Arithmetic overflow error converting expression to data type int. [SQLSTATE 22003] (Error 8115) The statement has been terminated.
[SQLSTATE 01000] (Error 3621). The step failed.

Apply stats_rollup_proc_mssql-vc2.5.zip as per http://kb.vmware.com/kb/1003732
http://kb.vmware.com/Platform/Publishing/attachments/1003732_fstats_rollup_proc_mssql-vc2.5.zip

Ensure database permissions are correct before upgrading VirtualCenter 2.0 to 2.5:

"If the sysadmin role is added to the VirtualCenter login to satisfy database permissions for the upgrade to VirtualCenter 2.5, the installer may install a parallel database making your original hosts, resources pools, clusters, and permissions unavailable."

Administrative Credentials Are Required for Oracle and SQL Server Databases When Installing or Upgrading VirtualCenter
http://kb.vmware.com/kb/1003052

Do not grant or revoke the System Administrator's role to satisfy database permission requirements when upgrading to VirtualCenter 2.5
http://kb.vmware.com/kb/1003346

Host And Other Configuration Data Missing After Upgrading to VirtualCenter 2.5
http://kb.vmware.com/kb/1003610

Statistics Rollup Stored Procedures—Optional Parameters and Diagnostics
http://kb.vmware.com/kb/3034858