Adjust Interrupt Moderation Profile in Regedit

Adjusting the interrupt moderation profile mappings for your network adapter through the Windows Registry allows you to balance CPU utilization and network packet processing latency. This guide explains how to locate your specific network interface card within the Registry Editor, identify the relevant interrupt moderation parameters, and modify the profile values to suit your performance requirements.

Step 1: Open the Registry Editor

1. Press Win + R to open the Run dialog box.
2. Type regedit and press Enter or click OK.
3. If prompted by User Account Control (UAC), click Yes to grant administrator privileges.

Step 2: Navigate to the Network Class Key

In the Registry Editor, navigate to the following path using the left sidebar:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4d36e972-e325-11ce-bfc1-08002be10318}

This GUID ({4d36e972-e325-11ce-bfc1-08002be10318}) contains subkeys for all network adapters installed on your system, labeled numerically as 0000, 0001, 0002, and so forth.

Step 3: Locate Your Network Adapter

1. Click on each numerical subkey (0000, 0001, etc.).
2. In the right pane, look at the DriverDesc string value.
3. Find the subkey where DriverDesc matches the name of your active network adapter (for example, Intel(R) Ethernet Controller I225-V or Realtek PCIe GbE Family Controller).

Step 4: Adjust Interrupt Moderation Settings

Depending on your network adapter driver and manufacturer, locate or create the following DWORD (32-bit) values inside the selected adapter subkey:

Enable or Disable Interrupt Moderation

• Name: *InterruptModeration
• Type: REG_SZ or REG_DWORD
• Values:
  • 0 = Disabled (reduces latency at the expense of higher CPU usage)
  • 1 = Enabled (reduces CPU usage by batching interrupts)

Adjust the Interrupt Moderation Rate / Profile Mapping

Adapter drivers (such as Intel or Realtek) often map interrupt moderation profiles to specific throttle rate values under parameters like *ITR or ITR:

• Name: *ITR or ITR
• Type: REG_DWORD or REG_SZ (match the existing entry type if already present)
• Common Profile Values (Decimal):
  • 0 = Off
  • 950 = Low (optimizes for lower latency)
  • 2000 = Medium (balanced)
  • 3600 = High (optimizes for network throughput and low CPU usage)
  • 65535 = Adaptive (dynamically adjusts based on traffic)

Note: If specific profile mapping keys (such as ITRProfile or RxIntDelay) already exist in your adapter subkey, double-click them to modify their base to Decimal and enter the desired profile value.

Step 5: Apply the Changes

1. Close the Registry Editor.
2. Restart your network adapter to apply the new settings:
   • Open Settings > Network & Internet > Advanced network settings.
   • Click Disable next to your adapter, wait a few seconds, then click Enable.
3. Alternatively, restart your computer to ensure all registry changes are fully loaded.