diff --git a/core/modules/migrate/migrate.services.yml b/core/modules/migrate/migrate.services.yml
index eecce2a8d1..9e1f8e94c7 100644
--- a/core/modules/migrate/migrate.services.yml
+++ b/core/modules/migrate/migrate.services.yml
@@ -43,4 +43,4 @@ services:
     class: Drupal\migrate\EventSubscriber\MemoryLimitExceeded
     tags:
       - { name: 'event_subscriber' }
-    arguments: ['@entity_type.manager', '@string_translation']
+    arguments: ['@entity_type.manager']
diff --git a/core/modules/migrate/src/Event/MigrateMemoryLimitEvent.php b/core/modules/migrate/src/Event/MigrateMemoryLimitEvent.php
index 12f3eeb2ea..bf700987c5 100644
--- a/core/modules/migrate/src/Event/MigrateMemoryLimitEvent.php
+++ b/core/modules/migrate/src/Event/MigrateMemoryLimitEvent.php
@@ -9,53 +9,19 @@
  */
 class MigrateMemoryLimitEvent extends Event {
 
-  /**
-   * The memory usage ratio.
-   *
-   * @var float
-   */
-  protected $usageRatio;
-
-  /**
-   * The memory usage in bytes.
-   *
-   * @var int
-   */
-  protected $usageInBytes;
-
-  /**
-   * The memory limit in bytes.
-   *
-   * @var int
-   */
-  protected $limit;
-
-  /**
-   * The phase of memory reclamation.
-   *
-   * The phases are defined in \Drupal\migrate\MemoryManagerInterface.
-   *
-   * @var string
-   */
-  protected $phase;
-
   /**
    * Constructs a memory limit event object.
    *
-   * @param float $usage_ratio
-   *   The usage ratio.
-   * @param int $usage_in_bytes
+   * @param float $usageRatio
+   *   The memory usage ratio.
+   * @param int $usageInBytes
    *   The memory usage in bytes.
    * @param int $limit
    *   The memory usage limit in bytes.
    * @param string $phase
    *   The phase of memory reclamation.
    */
-  public function __construct($usage_ratio, $usage_in_bytes, $limit, $phase) {
-    $this->usageRatio = $usage_ratio;
-    $this->usageInBytes = $usage_in_bytes;
-    $this->limit = $limit;
-    $this->phase = $phase;
+  public function __construct(protected float $usageRatio, protected int $usageInBytes, protected int $limit, protected string $phase) {
   }
 
   /**
@@ -64,7 +30,7 @@ public function __construct($usage_ratio, $usage_in_bytes, $limit, $phase) {
    * @return float
    *   The memory usage ratio.
    */
-  public function getUsageRatio() {
+  public function getUsageRatio(): float {
     return $this->usageRatio;
   }
 
@@ -74,7 +40,7 @@ public function getUsageRatio() {
    * @return int
    *   The memory usage in bytes.
    */
-  public function getUsageInBytes() {
+  public function getUsageInBytes(): int {
     return $this->usageInBytes;
   }
 
@@ -84,7 +50,7 @@ public function getUsageInBytes() {
    * @return int
    *   The memory limit in bytes.
    */
-  public function getLimit() {
+  public function getLimit(): int {
     return $this->limit;
   }
 
@@ -94,7 +60,7 @@ public function getLimit() {
    * @return string
    *   The phase of memory reclamation.
    */
-  public function getPhase() {
+  public function getPhase(): string {
     return $this->phase;
   }
 
diff --git a/core/modules/migrate/src/EventSubscriber/MemoryLimitExceeded.php b/core/modules/migrate/src/EventSubscriber/MemoryLimitExceeded.php
index 6ef4592464..8e8e7e9608 100644
--- a/core/modules/migrate/src/EventSubscriber/MemoryLimitExceeded.php
+++ b/core/modules/migrate/src/EventSubscriber/MemoryLimitExceeded.php
@@ -3,8 +3,7 @@
 namespace Drupal\migrate\EventSubscriber;
 
 use Drupal\Core\Entity\EntityTypeManagerInterface;
-use Drupal\Core\StringTranslation\StringTranslationTrait;
-use Drupal\Core\StringTranslation\TranslationInterface;
+use Drupal\Core\StringTranslation\TranslatableMarkup;
 use Drupal\migrate\Event\MigrateEvents;
 use Drupal\migrate\Event\MigrateMemoryLimitEvent;
 use Drupal\migrate\MemoryManagerInterface;
@@ -16,8 +15,6 @@
  */
 class MemoryLimitExceeded implements EventSubscriberInterface {
 
-  use StringTranslationTrait;
-
   /**
    * The migrate message class.
    *
@@ -26,31 +23,13 @@ class MemoryLimitExceeded implements EventSubscriberInterface {
   protected $message;
 
   /**
-   * The entity type manager.
-   *
-   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
-   */
-  protected $entityTypeManager;
-
-  /**
-   * The translation manager.
-   *
-   * @var \Drupal\Core\StringTranslation\TranslationInterface
-   */
-  protected $translationManager;
-
-  /**
-   * MemoryLimitExceeded constructor.
+   * Constructs MemoryLimitExceeded object.
    *
-   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
+   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entityTypeManager
    *   The entity type manager.
-   * @param \Drupal\Core\StringTranslation\TranslationInterface $translation_manager
-   *   The translation manager.
    */
-  public function __construct(EntityTypeManagerInterface $entity_type_manager, TranslationInterface $translation_manager) {
-    $this->entityTypeManager = $entity_type_manager;
+  public function __construct(protected EntityTypeManagerInterface $entityTypeManager) {
     $this->message = new MigrateMessage();
-    $this->setStringTranslation($translation_manager);
   }
 
   /**
@@ -71,7 +50,7 @@ public static function getSubscribedEvents() {
    * @throws \Drupal\Component\Plugin\Exception\InvalidPluginDefinitionException
    * @throws \Drupal\Component\Plugin\Exception\PluginNotFoundException
    */
-  public function reclaim(MigrateMemoryLimitEvent $event) {
+  public function reclaim(MigrateMemoryLimitEvent $event): void {
     if ($event->getPhase() != MemoryManagerInterface::PRE_RECLAIMED) {
       return;
     }
@@ -96,7 +75,7 @@ public function reclaim(MigrateMemoryLimitEvent $event) {
    * @param \Drupal\migrate\Event\MigrateMemoryLimitEvent $event
    *   A migrate memory limit event.
    */
-  public function notify(MigrateMemoryLimitEvent $event) {
+  public function notify(MigrateMemoryLimitEvent $event): void {
     $results = [
       '@pct' => round($event->getUsageRatio() * 100),
       '@usage' => format_size($event->getUsageInBytes()),
@@ -104,18 +83,18 @@ public function notify(MigrateMemoryLimitEvent $event) {
     ];
     switch ($event->getPhase()) {
       case MemoryManagerInterface::PRE_RECLAIMED:
-        $this->message->display($this->t(
+        $this->message->display(new TranslatableMarkup(
           'Memory usage is @usage (@pct% of limit @limit), reclaiming memory.', $results), 'warning');
         break;
 
       case MemoryManagerInterface::STILL_EXCEEDED:
-        $this->message->display($this->t(
+        $this->message->display(new TranslatableMarkup(
           'Memory usage is now @usage (@pct% of limit @limit), not enough reclaimed, starting new batch', $results), 'warning');
         break;
 
       case MemoryManagerInterface::REDUCED_ENOUGH_TO_CONTINUE:
       case '':
-        $this->message->display($this->t(
+        $this->message->display(new TranslatableMarkup(
           'Memory usage is now @usage (@pct% of limit @limit), reclaimed enough, continuing', $results));
         break;
     }
diff --git a/core/modules/migrate/src/MemoryManager.php b/core/modules/migrate/src/MemoryManager.php
index 7431c54b85..ddf00abc9f 100644
--- a/core/modules/migrate/src/MemoryManager.php
+++ b/core/modules/migrate/src/MemoryManager.php
@@ -12,66 +12,42 @@
  */
 class MemoryManager implements MemoryManagerInterface {
 
-  /**
-   * The ratio of the memory limit which will trigger a failed reclaim.
-   *
-   * @var float
-   */
-  protected $memoryReclaimThreshold;
-
-  /**
-   * The ratio of the memory limit at which an operation will be interrupted.
-   *
-   * @var float
-   */
-  protected $memoryThreshold;
-
   /**
    * The PHP memory limit expressed in bytes.
    *
    * @var int
    */
-  protected $memoryLimit;
-
-  /**
-   * The event dispatcher.
-   *
-   * @var \Symfony\Component\EventDispatcher\EventDispatcherInterface
-   */
-  protected $dispatcher;
+  protected int $memoryLimit;
 
   /**
    * MemoryManager constructor.
    *
    * @param \Symfony\Component\EventDispatcher\EventDispatcherInterface $dispatcher
    *   The event dispatcher.
-   * @param int $reclaim_threshold
+   * @param int $memoryReclaimThreshold
    *   The ratio of the memory limit which will trigger a failed reclaim.
-   * @param int $memory_threshold
+   * @param int $memoryThreshold
    *   The ratio of the memory limit at which an operation will be interrupted.
-   * @param int|string $memory_limit
+   * @param int|string|null $memory_limit
    *   The memory limit, either an integer or string size expressed as a number
    *   of bytes with optional SI or IEC binary unit prefix (e.g. 2, 3K, 5MB,
    *   10G, 6GiB, 8 bytes, 9mbytes).
    */
-  public function __construct(EventDispatcherInterface $dispatcher, $reclaim_threshold, $memory_threshold, $memory_limit = NULL) {
-    $this->dispatcher = $dispatcher;
-    $this->memoryReclaimThreshold = $reclaim_threshold;
-    $this->memoryThreshold = $memory_threshold;
-    // Record the memory limit in bytes.
-    if (empty($memory_limit)) {
+  public function __construct(protected EventDispatcherInterface $dispatcher, protected int $memoryReclaimThreshold, protected float $memoryThreshold, $memory_limit = NULL) {
+    if ($memory_limit === NULL) {
       // Auto detect memory limit.
       $memory_limit = trim(ini_get('memory_limit'));
     }
+    // Record the memory limit in bytes.
     $this->memoryLimit = ($memory_limit == -1)
       ? PHP_INT_MAX
-      : Bytes::toNumber($memory_limit);
+      : (int) Bytes::toNumber($memory_limit);
   }
 
   /**
    * {@inheritdoc}
    */
-  public function ensureMemory() {
+  public function ensureMemory(): bool {
     if (!$this->isLimitExceeded()) {
       return TRUE;
     }
@@ -92,7 +68,7 @@ public function ensureMemory() {
    * @param string $phase
    *   The memory phase.
    */
-  protected function dispatchEvent($phase) {
+  protected function dispatchEvent(string $phase): void {
     $event = new MigrateMemoryLimitEvent($this->getUsageRatio(), $this->getUsageInBytes(), $this->getLimit(), $phase);
     $this->dispatcher->dispatch($event, MigrateEvents::MEMORY_LIMIT);
   }
@@ -103,7 +79,7 @@ protected function dispatchEvent($phase) {
    * @return int
    *   The memory usage limit in bytes.
    */
-  protected function getLimit() {
+  protected function getLimit(): int {
     return $this->memoryLimit;
   }
 
@@ -113,7 +89,7 @@ protected function getLimit() {
    * @return int
    *   The memory usage.
    */
-  protected function getUsageInBytes() {
+  protected function getUsageInBytes(): int {
     return memory_get_usage();
   }
 
@@ -123,7 +99,7 @@ protected function getUsageInBytes() {
    * @return float|int
    *   The amount of memory used as a percentage.
    */
-  protected function getUsageRatio() {
+  protected function getUsageRatio(): float|int {
     return $this->getUsageInBytes() / $this->getLimit();
   }
 
@@ -138,7 +114,7 @@ protected function getUsageRatio() {
    * @return bool
    *   TRUE if the memory limit is exceeded, otherwise FALSE.
    */
-  protected function isLimitExceeded($multiplier = 1.0) {
+  protected function isLimitExceeded($multiplier = 1.0): bool {
     if (!$this->memoryThreshold) {
       return FALSE;
     }
diff --git a/core/modules/migrate/src/MemoryManagerInterface.php b/core/modules/migrate/src/MemoryManagerInterface.php
index 00ba0e94c9..8fcb152327 100644
--- a/core/modules/migrate/src/MemoryManagerInterface.php
+++ b/core/modules/migrate/src/MemoryManagerInterface.php
@@ -34,6 +34,6 @@ interface MemoryManagerInterface {
    *   TRUE if memory usage is low enough, or if enough memory can be reclaimed.
    *   FALSE if memory usage is too high and not enough can be reclaimed.
    */
-  public function ensureMemory();
+  public function ensureMemory(): bool;
 
 }
diff --git a/core/modules/migrate/src/MigrateExecutable.php b/core/modules/migrate/src/MigrateExecutable.php
index 6507b58f38..d05422bb50 100644
--- a/core/modules/migrate/src/MigrateExecutable.php
+++ b/core/modules/migrate/src/MigrateExecutable.php
@@ -39,13 +39,6 @@ class MigrateExecutable implements MigrateExecutableInterface {
    */
   protected $sourceRowStatus;
 
-  /**
-   * The memory manager.
-   *
-   * @var \Drupal\migrate\MemoryManagerInterface
-   */
-  protected $memoryManager;
-
   /**
    * The configuration values of the source.
    *
@@ -92,15 +85,18 @@ class MigrateExecutable implements MigrateExecutableInterface {
    *   (optional) The migrate message service.
    * @param \Symfony\Contracts\EventDispatcher\EventDispatcherInterface $event_dispatcher
    *   (optional) The event dispatcher.
-   * @param \Drupal\Migrate\MemoryManagerInterface $memory_manager
+   * @param \Drupal\Migrate\MemoryManagerInterface|null $memoryManager
    *   (optional) The memory manager.
    */
-  public function __construct(MigrationInterface $migration, MigrateMessageInterface $message = NULL, EventDispatcherInterface $event_dispatcher = NULL, MemoryManagerInterface $memory_manager = NULL) {
+  public function __construct(MigrationInterface $migration, MigrateMessageInterface $message = NULL, EventDispatcherInterface $event_dispatcher = NULL, protected ?MemoryManagerInterface $memoryManager = NULL) {
     $this->migration = $migration;
     $this->message = $message ?: new MigrateMessage();
     $this->getIdMap()->setMessage($this->message);
     $this->eventDispatcher = $event_dispatcher;
-    $this->memoryManager = $memory_manager;
+    if ($this->memoryManager === NULL) {
+      @trigger_error('Calling ' . __METHOD__ . '() without the $memoryManager argument is deprecated in drupal:10.1.0 and will be required in drupal:11.0.0. See https://www.drupal.org/node/3346839', E_USER_DEPRECATED);
+      $this->memoryManager = \Drupal::service('migrate.memory_manager');
+    }
   }
 
   /**
@@ -131,19 +127,6 @@ protected function getEventDispatcher() {
     return $this->eventDispatcher;
   }
 
-  /**
-   * Gets the migration memory manager.
-   *
-   * @return \Drupal\migrate\MemoryManagerInterface
-   *   The migration memory manager.
-   */
-  protected function getMemoryManager() {
-    if (!$this->memoryManager) {
-      $this->memoryManager = \Drupal::service('migrate.memory_manager');
-    }
-    return $this->memoryManager;
-  }
-
   /**
    * {@inheritdoc}
    */
@@ -513,7 +496,7 @@ protected function handleException(\Exception $exception, $save = TRUE) {
    * Checks for exceptional conditions, and display feedback.
    */
   protected function checkStatus() {
-    return $this->getMemoryManager()->ensureMemory()
+    return $this->memoryManager->ensureMemory()
       ? MigrationInterface::RESULT_COMPLETED
       : MigrationInterface::RESULT_INCOMPLETE;
   }