From 944c8993e889898cf5894b608571c39d974faa26 Mon Sep 17 00:00:00 2001
From: Cameron Gutman <aicommander@gmail.com>
Date: Tue, 11 Aug 2020 01:12:48 -0700
Subject: [PATCH] Elevate priorities for the UDP relay threads

---
 miss/miss.cpp  | 4 ++++
 miss/relay.cpp | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/miss/miss.cpp b/miss/miss.cpp
index d0f8810..0db1a1f 100644
--- a/miss/miss.cpp
+++ b/miss/miss.cpp
@@ -868,6 +868,10 @@ int Run()
 
     ResetLogFile();
 
+    // Bump the process priority class to above normal. The UDP relay threads will
+    // further raise their own thread priorities to avoid preemption by other activity.
+    SetPriorityClass(GetCurrentProcess(), ABOVE_NORMAL_PRIORITY_CLASS);
+
     // Create the UDP alternate port relays
     for (int i = 0; i < ARRAYSIZE(k_Ports); i++) {
         if (k_Ports[i].proto == IPPROTO_UDP) {
diff --git a/miss/relay.cpp b/miss/relay.cpp
index 1f2599a..a2465a4 100644
--- a/miss/relay.cpp
+++ b/miss/relay.cpp
@@ -21,6 +21,9 @@ UdpRelayThreadProc(LPVOID Context)
     PUDP_TUPLE tuple = (PUDP_TUPLE)Context;
     SOCKADDR_IN lastRemoteAddr;
 
+    // Ensure the relay threads aren't preempted by games or other CPU intensive activity
+    SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_HIGHEST);
+
     RtlZeroMemory(&lastRemoteAddr, sizeof(lastRemoteAddr));
 
     for (;;) {