--- old/src/os_cpu/linux_ppc/vm/os_linux_ppc.cpp	2016-11-16 16:45:37.152812000 +0100
+++ new/src/os_cpu/linux_ppc/vm/os_linux_ppc.cpp	2016-11-16 16:45:36.879795000 +0100
@@ -535,13 +535,15 @@
 ////////////////////////////////////////////////////////////////////////////////
 // thread stack
 
-size_t os::Posix::_compiler_thread_min_stack_allowed = 128 * K;
-size_t os::Posix::_java_thread_min_stack_allowed = 128 * K;
-size_t os::Posix::_vm_internal_thread_min_stack_allowed = 128 * K;
+// Minimum usable stack sizes required to get to user code. Space for VM
+// guard pages is added later.
+size_t os::Posix::_compiler_thread_min_stack_allowed = 64 * K;
+size_t os::Posix::_java_thread_min_stack_allowed = 64 * K;
+size_t os::Posix::_vm_internal_thread_min_stack_allowed = 64 * K;
 
-// return default stack size for thr_type
+// Return default stack size for thr_type.
 size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
-  // default stack size (compiler thread needs larger stack)
+  // Default stack size (compiler thread needs larger stack)
   size_t s = (thr_type == os::compiler_thread ? 4 * M : 1024 * K);
   return s;
 }
@@ -549,7 +551,7 @@
 size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
   // Creating guard page is very expensive. Java thread has HotSpot
   // guard page, only enable glibc guard page for non-Java threads.
-  return (thr_type == java_thread ? 0 : page_size());
+  return ((thr_type == java_thread || thr_type == os::compiler_thread) ? 0 : page_size());
 }
 
 // Java thread: