core/lib/Drupal/Core/Cache/DatabaseBackend.php | 24 ++++++++++++++++++++++++
 core/modules/system/system.install             | 11 +++++++++++
 2 files changed, 35 insertions(+)

diff --git a/core/lib/Drupal/Core/Cache/DatabaseBackend.php b/core/lib/Drupal/Core/Cache/DatabaseBackend.php
index d53c51c..eaa3b27 100644
--- a/core/lib/Drupal/Core/Cache/DatabaseBackend.php
+++ b/core/lib/Drupal/Core/Cache/DatabaseBackend.php
@@ -17,6 +17,16 @@
 class DatabaseBackend implements CacheBackendInterface {

   /**
+   * The number of cache items that this cache bin is allowed to store.
+   *
+   * @todo Bikeshed the size limit.
+   * @todo Make configurable per-bin.
+   *
+   * @var int
+   */
+  protected static $boundedSizeCount = 1000;
+
+  /**
    * @var string
    */
   protected $bin;
@@ -326,6 +336,14 @@ public function invalidateAll() {
    */
   public function garbageCollection() {
     try {
+      // Bounded size cache bin, using FIFO.
+      $query = $this->connection->select($this->bin);
+      $query->addExpression('MAX(bounded_id)', 'bounded_id');
+      $max_bounded_id = $query->execute()->fetchField();
+      $this->connection->delete($this->bin)
+        ->condition('bounded_id', $max_bounded_id - static::$boundedSizeCount, '<=')
+        ->execute();
+
       $this->connection->delete($this->bin)
         ->condition('expire', Cache::PERMANENT, '<>')
         ->condition('expire', REQUEST_TIME, '<')
@@ -469,11 +487,17 @@ public function schemaDefinition() {
           'length' => 255,
           'not null' => TRUE,
         ],
+        'bounded_id' => [
+          'type' => 'serial',
+        ],
       ],
       'indexes' => [
         'expire' => ['expire'],
       ],
       'primary key' => ['cid'],
+      'unique keys' => [
+        'bounded_id' => ['bounded_id'],
+      ]
     ];
     return $schema;
   }
diff --git a/core/modules/system/system.install b/core/modules/system/system.install
index 90e6291..e0c9633 100644
--- a/core/modules/system/system.install
+++ b/core/modules/system/system.install
@@ -1965,3 +1965,14 @@ function system_update_8400(&$sandbox) {

   $sandbox['#finished'] = $sandbox['current'] == $sandbox['max'];
 }
+
+/**
+ * Delete all cache_* tables. They are recreated on demand with the new schema.
+ */
+function system_update_8401() {
+  foreach (\Drupal\Core\Cache\Cache::getBins() as $bin => $cache_backend) {
+    if ($cache_backend instanceof \Drupal\Core\Cache\DatabaseBackend) {
+      db_drop_table("cache_$bin");
+    }
+  }
+}