From b93bf456b55ee3b52c28a6681edec01b3f26f541 Mon Sep 17 00:00:00 2001
From: imterah <me@terah.dev>
Date: Fri, 21 Mar 2025 13:17:08 -0400
Subject: [PATCH] fix: Fixes 100% CPU usage in the backend runtime

This makes the backend runtime not constantly search for messages to be
processed. Instead, it only wakes up when it needs to be woken up via
goroutines.
---
 backend/api/backendruntime/runtime.go | 13 +++++++++++++
 backend/api/backendruntime/struct.go  | 13 ++++++++-----
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/backend/api/backendruntime/runtime.go b/backend/api/backendruntime/runtime.go
index 52e280d..8d5ca7a 100644
--- a/backend/api/backendruntime/runtime.go
+++ b/backend/api/backendruntime/runtime.go
@@ -15,6 +15,9 @@ import (
 	"github.com/charmbracelet/log"
 )
 
+// TODO TODO TODO(imterah):
+// This code is a mess. This NEEDS to be rearchitected and refactored to work better. Or at the very least, this code needs to be documented heavily.
+
 func handleCommand(command interface{}, sock net.Conn, rtcChan chan interface{}) error {
 	bytes, err := commonbackend.Marshal(command)
 
@@ -160,6 +163,9 @@ func (runtime *Runtime) goRoutineHandler() error {
 
 		OuterLoop:
 			for {
+				_ = <-runtime.startProcessingNotification
+				runtime.isRuntimeCurrentlyProcessing = true
+
 				for chanIndex, messageData := range runtime.messageBuffer {
 					if messageData == nil {
 						continue
@@ -177,6 +183,8 @@ func (runtime *Runtime) goRoutineHandler() error {
 
 					runtime.messageBuffer[chanIndex] = nil
 				}
+
+				runtime.isRuntimeCurrentlyProcessing = false
 			}
 
 			sock.Close()
@@ -235,6 +243,7 @@ func (runtime *Runtime) Start() error {
 	runtime.messageBuffer = make([]*messageForBuf, 10)
 	runtime.messageBufferLock = sync.Mutex{}
 
+	runtime.startProcessingNotification = make(chan bool)
 	runtime.processRestartNotification = make(chan bool, 1)
 
 	runtime.logger = &writeLogger{
@@ -322,6 +331,10 @@ SchedulingLoop:
 		schedulingAttempts++
 	}
 
+	if !runtime.isRuntimeCurrentlyProcessing {
+		runtime.startProcessingNotification <- true
+	}
+
 	// Fetch response and close Channel
 	response, ok := <-commandChannel
 
diff --git a/backend/api/backendruntime/struct.go b/backend/api/backendruntime/struct.go
index cd30182..cd4b3b8 100644
--- a/backend/api/backendruntime/struct.go
+++ b/backend/api/backendruntime/struct.go
@@ -16,15 +16,18 @@ type Backend struct {
 
 type messageForBuf struct {
 	Channel chan interface{}
+	// TODO(imterah): could this be refactored to just be a []byte instead? Look into this
 	Message interface{}
 }
 
 type Runtime struct {
-	isRuntimeRunning           bool
-	logger                     *writeLogger
-	currentProcess             *exec.Cmd
-	currentListener            net.Listener
-	processRestartNotification chan bool
+	isRuntimeRunning             bool
+	isRuntimeCurrentlyProcessing bool
+	startProcessingNotification  chan bool
+	logger                       *writeLogger
+	currentProcess               *exec.Cmd
+	currentListener              net.Listener
+	processRestartNotification   chan bool
 
 	messageBufferLock sync.Mutex
 	messageBuffer     []*messageForBuf