From c6c4428f7d4abc64626e65c96a3899b69b7498aa Mon Sep 17 00:00:00 2001
From: Thomas <thomas@ajnart.fr>
Date: Wed, 15 Jul 2026 14:55:18 +0200
Subject: [PATCH] Revert "fix(docker): report current CPU usage instead of the
 lifetime average" (#6357)

---
 packages/request-handler/src/docker.ts        | 21 ++++---------------
 .../request-handler/src/test/docker.spec.ts   | 20 ------------------
 2 files changed, 4 insertions(+), 37 deletions(-)

diff --git a/packages/request-handler/src/docker.ts b/packages/request-handler/src/docker.ts
index a238b4a3c..12a78c05a 100644
--- a/packages/request-handler/src/docker.ts
+++ b/packages/request-handler/src/docker.ts
@@ -300,10 +300,7 @@ async function getContainersWithStatsAsync() {
 
     const stats = await instance
       .getContainer(container.Id)
-      // Not in one-shot mode: the daemon then includes precpu_stats (the
-      // previous reading), which is required to compute the current CPU usage
-      // as a delta. One-shot omits it and would only expose lifetime totals.
-      .stats({ stream: false })
+      .stats({ stream: false, "one-shot": true })
       .catch(
         () =>
           ({
@@ -339,22 +336,12 @@ export function calculateCpuUsage(stats: ContainerStats): number {
   }
 
   const numberOfCpus = stats.cpu_stats.online_cpus;
-
-  // Docker's own formula for the current (instantaneous) CPU usage: it compares
-  // the latest reading against the previous one (precpu_stats). Dividing the
-  // cumulative total_usage by the cumulative system_cpu_usage instead would
-  // report the container's lifetime average, which stays high long after a load
-  // spike has ended. precpu_stats is only present when the stats are NOT fetched
-  // in one-shot mode; when it is absent (e.g. Podman) the deltas fall back to the
-  // cumulative totals, matching the previous behaviour.
-  const cpuDelta = stats.cpu_stats.cpu_usage.total_usage - (stats.precpu_stats?.cpu_usage?.total_usage ?? 0);
-  const systemDelta = (stats.cpu_stats.system_cpu_usage ?? 0) - (stats.precpu_stats?.system_cpu_usage ?? 0);
-
-  if (systemDelta <= 0 || cpuDelta < 0) {
+  const usage = stats.cpu_stats.system_cpu_usage;
+  if (!usage || usage === 0) {
     return 0;
   }
 
-  return (cpuDelta / systemDelta) * numberOfCpus * 100;
+  return (stats.cpu_stats.cpu_usage.total_usage / usage) * numberOfCpus * 100;
 }
 
 export function calculateMemoryUsage(stats: ContainerStats): number {
diff --git a/packages/request-handler/src/test/docker.spec.ts b/packages/request-handler/src/test/docker.spec.ts
index 12dbb347b..b4e34f816 100644
--- a/packages/request-handler/src/test/docker.spec.ts
+++ b/packages/request-handler/src/test/docker.spec.ts
@@ -75,26 +75,6 @@ describe("calculateCpuUsage", () => {
     // (500 / 100000) * 2 * 100 = 1
     expect(calculateCpuUsage(stats)).toBe(1);
   });
-
-  test("should use the delta against precpu_stats for the current usage", () => {
-    const stats = createStats({
-      cpu_stats: { online_cpus: 4, cpu_usage: { total_usage: 1_002_000 }, system_cpu_usage: 20_000 },
-      precpu_stats: { cpu_usage: { total_usage: 1_000_000 }, system_cpu_usage: 10_000 },
-    });
-    // Despite a large lifetime total_usage, only the recent delta counts:
-    // (2000 / 10000) * 4 * 100 = 80
-    expect(calculateCpuUsage(stats)).toBe(80);
-  });
-
-  test("should report 0 for a container that was busy over its lifetime but is idle now", () => {
-    const stats = createStats({
-      cpu_stats: { online_cpus: 4, cpu_usage: { total_usage: 1_000_000 }, system_cpu_usage: 20_000 },
-      precpu_stats: { cpu_usage: { total_usage: 1_000_000 }, system_cpu_usage: 10_000 },
-    });
-    // No CPU delta since the last reading -> current usage is 0, even though the
-    // lifetime average would be high. This is the regression the fix addresses.
-    expect(calculateCpuUsage(stats)).toBe(0);
-  });
 });
 
 describe("calculateMemoryUsage", () => {