diff --git a/src/cpu-profiler.cc b/src/cpu-profiler.cc
index 953952a91d..3cbac77858 100644
--- a/src/cpu-profiler.cc
+++ b/src/cpu-profiler.cc
@@ -1,4 +1,4 @@
-// Copyright 2010 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -42,7 +42,7 @@ namespace internal {
 static const int kEventsBufferSize = 256 * KB;
 static const int kTickSamplesBufferChunkSize = 64 * KB;
 static const int kTickSamplesBufferChunksCount = 16;
-static const int kProfilerStackSize = 32 * KB;
+static const int kProfilerStackSize = 64 * KB;
 
 
 ProfilerEventsProcessor::ProfilerEventsProcessor(ProfileGenerator* generator)
diff --git a/src/platform-freebsd.cc b/src/platform-freebsd.cc
index c6dedd4ad2..a5981b19c3 100644
--- a/src/platform-freebsd.cc
+++ b/src/platform-freebsd.cc
@@ -710,7 +710,7 @@ class SignalSender : public Thread {
     FULL_INTERVAL
   };
 
-  static const int kSignalSenderStackSize = 32 * KB;
+  static const int kSignalSenderStackSize = 64 * KB;
 
   explicit SignalSender(int interval)
       : Thread(Thread::Options("SignalSender", kSignalSenderStackSize)),
diff --git a/src/platform-linux.cc b/src/platform-linux.cc
index 537637ccee..14297483c3 100644
--- a/src/platform-linux.cc
+++ b/src/platform-linux.cc
@@ -1060,7 +1060,7 @@ class SignalSender : public Thread {
     FULL_INTERVAL
   };
 
-  static const int kSignalSenderStackSize = 32 * KB;
+  static const int kSignalSenderStackSize = 64 * KB;
 
   explicit SignalSender(int interval)
       : Thread(Thread::Options("SignalSender", kSignalSenderStackSize)),
diff --git a/src/platform-macos.cc b/src/platform-macos.cc
index f061f67a40..e367d21a41 100644
--- a/src/platform-macos.cc
+++ b/src/platform-macos.cc
@@ -733,7 +733,7 @@ class Sampler::PlatformData : public Malloced {
 
 class SamplerThread : public Thread {
  public:
-  static const int kSamplerThreadStackSize = 32 * KB;
+  static const int kSamplerThreadStackSize = 64 * KB;
 
   explicit SamplerThread(int interval)
       : Thread(Thread::Options("SamplerThread", kSamplerThreadStackSize)),
diff --git a/src/platform-openbsd.cc b/src/platform-openbsd.cc
index 96dece0146..7e27a01d45 100644
--- a/src/platform-openbsd.cc
+++ b/src/platform-openbsd.cc
@@ -782,7 +782,7 @@ class SignalSender : public Thread {
     FULL_INTERVAL
   };
 
-  static const int kSignalSenderStackSize = 32 * KB;
+  static const int kSignalSenderStackSize = 64 * KB;
 
   explicit SignalSender(int interval)
       : Thread(Thread::Options("SignalSender", kSignalSenderStackSize)),
diff --git a/src/platform-solaris.cc b/src/platform-solaris.cc
index 85a420350b..349da01edc 100644
--- a/src/platform-solaris.cc
+++ b/src/platform-solaris.cc
@@ -704,7 +704,7 @@ class SignalSender : public Thread {
     FULL_INTERVAL
   };
 
-  static const int kSignalSenderStackSize = 32 * KB;
+  static const int kSignalSenderStackSize = 64 * KB;
 
   explicit SignalSender(int interval)
       : Thread(Thread::Options("SignalSender", kSignalSenderStackSize)),
diff --git a/src/platform-win32.cc b/src/platform-win32.cc
index 52bc3f569c..f16b5e74fd 100644
--- a/src/platform-win32.cc
+++ b/src/platform-win32.cc
@@ -1894,7 +1894,7 @@ class Sampler::PlatformData : public Malloced {
 
 class SamplerThread : public Thread {
  public:
-  static const int kSamplerThreadStackSize = 32 * KB;
+  static const int kSamplerThreadStackSize = 64 * KB;
 
   explicit SamplerThread(int interval)
       : Thread(Thread::Options("SamplerThread", kSamplerThreadStackSize)),
diff --git a/test/cctest/test-mark-compact.cc b/test/cctest/test-mark-compact.cc
index 9de069d87f..2535f10c03 100644
--- a/test/cctest/test-mark-compact.cc
+++ b/test/cctest/test-mark-compact.cc
@@ -1,4 +1,4 @@
-// Copyright 2006-2008 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -534,15 +534,15 @@ TEST(BootUpMemoryUse) {
     intptr_t booted_memory = MemoryInUse();
     if (sizeof(initial_memory) == 8) {
       if (v8::internal::Snapshot::IsEnabled()) {
-        CHECK_LE(booted_memory - initial_memory, 6654 * 1024);  // 6444.
+        CHECK_LE(booted_memory - initial_memory, 6686 * 1024);  // 6476.
       } else {
-        CHECK_LE(booted_memory - initial_memory, 6777 * 1024);  // 6596.
+        CHECK_LE(booted_memory - initial_memory, 6809 * 1024);  // 6628.
       }
     } else {
       if (v8::internal::Snapshot::IsEnabled()) {
-        CHECK_LE(booted_memory - initial_memory, 6500 * 1024);  // 6356.
+        CHECK_LE(booted_memory - initial_memory, 6532 * 1024);  // 6388.
       } else {
-        CHECK_LE(booted_memory - initial_memory, 6654 * 1024);  // 6424
+        CHECK_LE(booted_memory - initial_memory, 6686 * 1024);  // 6456
       }
     }
   }