From c5cb01527603dea385d698f9cf4c7d2c17dca616 Mon Sep 17 00:00:00 2001
From: Jason Jean <jasonjean1993@gmail.com>
Date: Fri, 27 Sep 2024 10:04:38 -0400
Subject: [PATCH] fix(core): calculate project dependencies upfront in the
 schedule (#28152)

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## Current Behavior
<!-- This is the behavior we have today -->

Counting project dependencies during the sort resulted in a lot of
duplicate work.

## Expected Behavior
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-->

Count project dependencies for all tasks up front.. so that this
information can be easily accessed during the sort.

## Related Issue(s)
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merged. -->

Fixes #
---
 .../nx/src/tasks-runner/tasks-schedule.ts     | 20 +++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/packages/nx/src/tasks-runner/tasks-schedule.ts b/packages/nx/src/tasks-runner/tasks-schedule.ts
index 97ce3f6304f52..3374c536314a1 100644
--- a/packages/nx/src/tasks-runner/tasks-schedule.ts
+++ b/packages/nx/src/tasks-runner/tasks-schedule.ts
@@ -28,6 +28,7 @@ export class TasksSchedule {
   private completedTasks = new Set<string>();
   private scheduleRequestsExecutionChain = Promise.resolve();
   private estimatedTaskTimings: Record<string, number> = {};
+  private projectDependencies: Record<string, number> = {};
 
   constructor(
     private readonly projectGraph: ProjectGraph,
@@ -42,6 +43,15 @@ export class TasksSchedule {
           Object.values(this.taskGraph.tasks).map((t) => t.target)
         );
     }
+
+    for (const project of Object.values(this.taskGraph.tasks).map(
+      (t) => t.target.project
+    )) {
+      this.projectDependencies[project] ??= findAllProjectNodeDependencies(
+        project,
+        this.reverseProjectGraph
+      ).length;
+    }
   }
 
   public async scheduleNextTasks() {
@@ -125,14 +135,8 @@ export class TasksSchedule {
         const project1 = this.taskGraph.tasks[taskId1].target.project;
         const project2 = this.taskGraph.tasks[taskId2].target.project;
 
-        const project1NodeDependencies = findAllProjectNodeDependencies(
-          project1,
-          this.reverseProjectGraph
-        ).length;
-        const project2NodeDependencies = findAllProjectNodeDependencies(
-          project2,
-          this.reverseProjectGraph
-        ).length;
+        const project1NodeDependencies = this.projectDependencies[project1];
+        const project2NodeDependencies = this.projectDependencies[project2];
 
         const dependenciesDiff =
           project2NodeDependencies - project1NodeDependencies;