diff --git a/app/Traits/HasMetrics.php b/app/Traits/HasMetrics.php
index cc096fd1e3..d39675276d 100644
--- a/app/Traits/HasMetrics.php
+++ b/app/Traits/HasMetrics.php
@@ -172,6 +172,11 @@ trait HasMetrics
     /**
      * Map raw rows to [timestampMs, value] pairs, downsampling long ranges.
      *
+     * Sentinel keeps raw samples for the last 24 to 48 hours and one-minute averages
+     * before that. LTTB buckets by point count, so on ranges that reach past the raw
+     * window the raw part got most of the chart points. Those ranges are averaged per
+     * minute first, the same as Sentinel does, so the density is even over time.
+     *
      * @param  array<int, array<string, mixed>>|null  $rows
      */
     private function mapRows(?array $rows, string $valueField, int $mins): ?array
@@ -184,6 +189,10 @@ trait HasMetrics
             return [(int) $metric['time'], (float) ($metric[$valueField] ?? 0.0)];
         })->toArray();
 
+        if ($mins > 24 * 60) {
+            $metrics = $this->averagePerMinute($metrics);
+        }
+
         if ($mins > 60 && count($metrics) > 1000) {
             $metrics = downsampleLTTB($metrics, 1000);
         }
@@ -191,6 +200,28 @@ trait HasMetrics
         return $metrics;
     }
 
+    /**
+     * Average [timestampMs, value] pairs into one-minute buckets, timestamped at the
+     * bucket start like Sentinel's own downsampling. Samples that are a minute or more
+     * apart keep their own value.
+     *
+     * @param  array<int, array{0: int, 1: float}>  $metrics
+     * @return array<int, array{0: int, 1: float}>
+     */
+    private function averagePerMinute(array $metrics): array
+    {
+        $sums = [];
+        $counts = [];
+        foreach ($metrics as [$time, $value]) {
+            $bucket = intdiv($time, 60_000) * 60_000;
+            $sums[$bucket] = ($sums[$bucket] ?? 0.0) + $value;
+            $counts[$bucket] = ($counts[$bucket] ?? 0) + 1;
+        }
+        ksort($sums);
+
+        return array_map(fn (int $bucket) => [$bucket, $sums[$bucket] / $counts[$bucket]], array_keys($sums));
+    }
+
     private function metricsToken(Server $server): string
     {
         $previousToken = null;
diff --git a/tests/Feature/ServerMetricsPrefetchTest.php b/tests/Feature/ServerMetricsPrefetchTest.php
index ca1d6eeab8..85a51e1ac4 100644
--- a/tests/Feature/ServerMetricsPrefetchTest.php
+++ b/tests/Feature/ServerMetricsPrefetchTest.php
@@ -85,3 +85,25 @@ it('runs the batched metrics script with sudo for a non-root user', function ()
         ->and($commands[0])->not->toContain('sudo curl')
         ->and($commands[0])->not->toContain('sudo printf');
 });
+
+it('keeps long-range charts evenly dense across mixed-resolution Sentinel history', function () {
+    // Sentinel keeps raw samples (here every 10 s) for the last one to two days and
+    // one-minute averages before that. A 7-day chart must not crowd the raw days.
+    $end = 1_800_000_000_000;
+    $rawStart = $end - 2 * 86_400_000;
+    $rows = [];
+    for ($time = $end - 7 * 86_400_000; $time < $rawStart; $time += 60_000) {
+        $rows[] = ['time' => $time, 'percent' => 10];
+    }
+    for ($time = $rawStart; $time < $end; $time += 10_000) {
+        $rows[] = ['time' => $time, 'percent' => ($time / 10_000) % 2 === 0 ? 0 : 20];
+    }
+    Process::fake(fn () => Process::result(json_encode($rows)));
+
+    $metrics = $this->server->getCpuMetrics(10080);
+    $recent = array_filter($metrics, fn (array $point) => $point[0] >= $rawStart);
+
+    expect(count($metrics))->toBeLessThanOrEqual(1000)
+        ->and(count($recent) / count($metrics))->toBeLessThan(0.35)
+        ->and(array_values(array_unique(array_column($recent, 1))))->toBe([10.0]);
+});