Disable MSI mode support

https://support.microsoft.com/en-us/help/3083595/task-manager-might-show-100-disk-utilization-on-windows-10-devices-wit

Task Manager might show 100% disk utilization on Windows 10 devices with Message Signaled Interrupt (MSI) mode enabled

Applies to: Windows 10

Symptoms

Task Manager shows the disk to be at 100% utilization despite a light or no workload, and the system may experience lag or become unresponsive. In addition, the system event log contains numerous events with Event ID 129, which represent resets of the disk controller.

While device resets can be caused by a varying number of factors, we are aware of issues with some Advanced Host Controller Interface PCI-Express(AHCI PCIe) models that causes these symptoms in Windows 10 when running with the inbox StorAHCI.sys driver. Due to a firmware bug, the Solid-state drive (SSD) does not properly complete input/output when Message Signaled Interrupt (MSI) mode is enabled. As a result, the Windows storage stack attempts to reset the device after waiting on unresponsive reads or writes for a period of time.

MSI mode can be disabled for specific devices via the registry:

Identify if you are running the inbox AHCI driver (StorAHCI.sys):
1. Open a command prompt with administrator privileges. Then type the following command in the command prompt window and hit Enter: devmgmt.msc
2. Under IDE ATA/ATAPI Controllers right-click on the AHCI controller node and select Properties. This node is usually called “Standard SATA AHCI Controller.”
3. Navigate to the driver tab and click Driver Details.
4. If you see “StorAHCI.sys” in the list, you are running the inbox driver.
Disable MSI for the controller in the registry:
1. In the same properties window opened in step 1.2, navigate to the Details tab and select Device instance path from the Property drop-down menu. Note this path.
2. Open the registry editor by typing regedit in the previously opened command prompt.
3. Navigate to: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Enum\PCI\ <AHCI Controller>\Device Parameters\Interrupt Management\MessageSignaledInterruptProperties, where <AHCI Controller> refers to the device instance path you noted in step 2.1.
4. Change the value of the MSISupported key from “1” to “0”.
5. If you don’t know which controller your boot device is attached to, repeat steps 2.1 through 2.4 for all AHCI controllers found under 1.2.
Reboot the machine.

Last Updated: Jul 29, 2015

Practice:
1. Right-click My Computer, click the Manage button -> System Tools -> Event Viewer -> Windows Logs -> System, right-click all the log as a text, after searching 129, if there is the following data:

Warning 2017/1/23 15: 37: 45storahci 129 without resetting the device issued Device \ \ RaidPort0 of.

Description is the question:

When using StorAHCI.sys drive some AHCI mode, it may not lead to individual SSD in the "Message Signaled Interrupt" to complete the correct input / output operations under (MSI) mode, the final performance of the system is stalled. Of course, the solution is to close it (MSI Mode) directly in regedit.

2. Right-click My Computer, click the Manage button -> System Tools -> Device Manager -> IDE ATA / ATAPI controllers -> AHCI controller, right-click Properties, select the details information, property (P) select the device in real-time path, you can see the path pATH;

3.win + R key to open operation, an input regedit, open the registry editor, find the path HKEY_LOCAL_MACHINE \ System \ CurrentControlSet \ Enum \ PCI \ <AHCI Controller> (2 inside the PATH) \ Device Parameters \ Interrupt Management \ MessageSignaledInterruptProperties;

4 can be seen in the right pane "MSISupported" key, from 1 to 0;

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