The log file size grows larger than the maximum file size limit that was set in Performance Monitor if you select a Comma Separated log format or a Tab Separated log format on a computer that is running Windows Server 2008 or Windows Vista
Consider the following scenario:
- You use the Data Collector Sets feature in Performance Monitor (Perfmon.exe) to collect data.
- In the Properties dialog box of a data collector set, you set a value in the Maximum Size field that is located on the Stop Condition tab. For example, you set a value of 30 megabytes (MB).
- In the Properties dialog box of a created data collector that is in the data collector set, you select Comma Separated or Tab Separated in the Log format list.
- You use Performance Monitor to collect performance counters and to save them to a log file.
In this scenario, the maximum file size limit that you set in the Maximum Size field does not work. Therefore, the log file size keeps growing over the maximum file size limit.
For more information on this issue, including potential causes, workarounds, and resolutions, see: Microsoft KB Article KB974248.