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',],
       }],