diff --git a/common.gypi b/common.gypi
index 3161adbe09087a..4e645cf50671d4 100644
--- a/common.gypi
+++ b/common.gypi
@@ -36,7 +36,7 @@
 
     # Reset this number to 0 on major V8 upgrades.
     # Increment by one for each non-official patch applied to deps/v8.
-    'v8_embedder_string': '-node.9',
+    'v8_embedder_string': '-node.10',
 
     ##### V8 defaults for Node.js #####
 
diff --git a/deps/v8/BUILD.gn b/deps/v8/BUILD.gn
index 96e4fee3f6cf80..68d92c3477bc2c 100644
--- a/deps/v8/BUILD.gn
+++ b/deps/v8/BUILD.gn
@@ -83,6 +83,17 @@ declare_args() {
   # Sets -dENABLE_HUGEPAGE
   v8_enable_hugepage = false
 
+  # Sets -dV8_ENABLE_PRIVATE_MAPPING_FORK_OPTIMIZATION.
+  #
+  # This flag speeds up the performance of fork/execve on Linux systems for
+  # embedders which use it (like Node.js). It works by marking the pages that
+  # V8 allocates as MADV_DONTFORK. Without MADV_DONTFORK, the Linux kernel
+  # spends a long time manipulating page mappings on fork and exec which the
+  # child process doesn't generally need to access.
+  #
+  # See v8:7381 for more details.
+  v8_enable_private_mapping_fork_optimization = false
+
   # Sets -dENABLE_HANDLE_ZAPPING.
   v8_enable_handle_zapping = is_asan || is_debug
 
@@ -971,6 +982,9 @@ config("features") {
   if (v8_enable_hugepage) {
     defines += [ "ENABLE_HUGEPAGE" ]
   }
+  if (v8_enable_private_mapping_fork_optimization) {
+    defines += [ "V8_ENABLE_PRIVATE_MAPPING_FORK_OPTIMIZATION" ]
+  }
   if (v8_enable_object_print) {
     defines += [ "OBJECT_PRINT" ]
   }
diff --git a/deps/v8/src/base/platform/platform-posix.cc b/deps/v8/src/base/platform/platform-posix.cc
index 40e870a346f885..4b6e6ad8f17138 100644
--- a/deps/v8/src/base/platform/platform-posix.cc
+++ b/deps/v8/src/base/platform/platform-posix.cc
@@ -158,6 +158,12 @@ void* Allocate(void* hint, size_t size, OS::MemoryPermission access,
   int flags = GetFlagsForMemoryPermission(access, page_type);
   void* result = mmap(hint, size, prot, flags, kMmapFd, kMmapFdOffset);
   if (result == MAP_FAILED) return nullptr;
+
+#if V8_ENABLE_PRIVATE_MAPPING_FORK_OPTIMIZATION
+  // This is advisory, so we ignore errors.
+  madvise(result, size, MADV_DONTFORK);
+#endif
+
 #if ENABLE_HUGEPAGE
   if (result != nullptr && size >= kHugePageSize) {
     const uintptr_t huge_start =
diff --git a/tools/v8_gypfiles/features.gypi b/tools/v8_gypfiles/features.gypi
index 7e71e9c46790ab..3a7f355ef8021b 100644
--- a/tools/v8_gypfiles/features.gypi
+++ b/tools/v8_gypfiles/features.gypi
@@ -72,7 +72,21 @@
         'v8_enable_etw_stack_walking': 1,
       }, {
         'v8_enable_etw_stack_walking': 0,
-      }]
+      }],
+      ['OS=="linux"', {
+        # Sets -dV8_ENABLE_PRIVATE_MAPPING_FORK_OPTIMIZATION.
+        #
+        # This flag speeds up the performance of fork/execve on Linux systems for
+        # embedders which use it (like Node.js). It works by marking the pages that
+        # V8 allocates as MADV_DONTFORK. Without MADV_DONTFORK, the Linux kernel
+        # spends a long time manipulating page mappings on fork and exec which the
+        # child process doesn't generally need to access.
+        #
+        # See v8:7381 for more details.
+        'v8_enable_private_mapping_fork_optimization': 1,
+      }, {
+        'v8_enable_private_mapping_fork_optimization': 0,
+      }],
     ],
     'is_debug%': 0,
 
@@ -320,6 +334,9 @@
       ['v8_enable_hugepage==1', {
         'defines': ['ENABLE_HUGEPAGE',],
       }],
+      ['v8_enable_private_mapping_fork_optimization==1', {
+        'defines': ['V8_ENABLE_PRIVATE_MAPPING_FORK_OPTIMIZATION'],
+      }],
       ['v8_enable_vtunejit==1', {
         'defines': ['ENABLE_VTUNE_JIT_INTERFACE',],
       }],