Hard Disk Monitoring

This is a weird one. I bought HD M recently and followed the instructions for activating the disk performance measurements. In particular, setting the registry key (in Win 7) "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Perfdisk\Performance\disable performance counters" to 0 (zero).
This works perfectly for SSD and HDDs (internal). In fact, to make the counters permanent I removed that registry entry completely, as mentioned somewhere in one of the papers linked to by the HD S FAQ.

So far, so good. However, I have found tonight that on boot, Windows 7 either flips that registry entry to 1, thus disabling it, or, if the registry entry is removed completely, something in Windows replaces it. I have to modify the registry each time I start HD S, in order to see the counts. Tonight I found this happening even during hibernation! When I hibernated the system the counts were displayed. When I restarted, the registry entry had been re-entered into the registry and set back to 1.

As far as I can tell, the other services connected with measurements (WMI) are running, and Perfmon can see the counters and display the graphs.

Any ideas on how to make the registry item stick? I figure something else is disabling that registry entry on booting.

Robin

Actually, WMI (Management Instrumentation, was set to 'manual' when I first looked at it. its description says, in part, "If WMI is not running, it automatically starts when the first management application or script requests connection to a WMI namespace."

I set it to 'automatic' and the counters are now permanently on, and the registry entry has survived several boots.

Does Sentinel make calls to WMI?

I can confirm WMI is completely independent from the performance counter objects.

Yes, Hard Disk Sentinel uses WMI to detect and report some kind of information on the actual system - but does not rely on it heavily.
Hard Disk Sentinel can work without problems (even with real time performance monitoring) if WMI is not available.

The problem is that in some rare cases, Windows may disable performance monitoring on some specific events, for example hibernation and/or inserting a removable device. If that happens, Hard Disk Sentinel asks WIndows to re-build the performance counter object cache - to display performance information for the new situation. This may be disabled as described in the F.A.Q. page:

http://www.hdsentinel.com/faq.php#perf

see the "Update..." section by creating a new STRING key named DisablePerfCacheClear and specify value of 1 for that.