diff --git a/base-codezero/src/core/include/platform_thread.h b/base-codezero/src/core/include/platform_thread.h
index 707bd0b6b..e46554b08 100644
--- a/base-codezero/src/core/include/platform_thread.h
+++ b/base-codezero/src/core/include/platform_thread.h
@@ -136,6 +136,11 @@ namespace Genode {
 			 */
 			void affinity(unsigned cpu);
 
+			/**
+			 * Get the executing CPU for this thread
+			 */
+			unsigned affinity();
+
 			/**
 			 * Get thread name
 			 */
diff --git a/base-codezero/src/core/platform_thread.cc b/base-codezero/src/core/platform_thread.cc
index cd77024e3..a09ef3142 100644
--- a/base-codezero/src/core/platform_thread.cc
+++ b/base-codezero/src/core/platform_thread.cc
@@ -29,7 +29,14 @@ using namespace Codezero;
 
 void Platform_thread::affinity(unsigned int cpu_no)
 {
-	PDBG("not yet implemented");
+	PDBG("'%s' not yet implemented", __PRETTY_FUNCTION__);
+}
+
+
+unsigned Platform_thread::affinity()
+{
+	PDBG("'%s' not yet implemented", __PRETTY_FUNCTION__);
+	return 0;
 }
 
 
diff --git a/base-fiasco/src/core/include/platform_thread.h b/base-fiasco/src/core/include/platform_thread.h
index 90af57bdd..742d46a29 100644
--- a/base-fiasco/src/core/include/platform_thread.h
+++ b/base-fiasco/src/core/include/platform_thread.h
@@ -123,6 +123,11 @@ namespace Genode {
 			 */
 			void affinity(unsigned) { }
 
+			/**
+			 * Request the affinity of this thread
+			 */
+			unsigned affinity() { return 0; }
+
 			/**
 			 * Return the address space to which the thread is bound
 			 */
diff --git a/base-fiasco/src/core/platform.cc b/base-fiasco/src/core/platform.cc
index 4636bd25f..41dfca0e5 100644
--- a/base-fiasco/src/core/platform.cc
+++ b/base-fiasco/src/core/platform.cc
@@ -130,7 +130,7 @@ static void _core_pager_loop()
 }
 
 
-Platform::Sigma0::Sigma0() : Pager_object(0)
+Platform::Sigma0::Sigma0() : Pager_object(0, 0)
 {
 	cap(reinterpret_cap_cast<Cpu_thread>(Native_capability(Fiasco::sigma0_threadid, 0)));
 }
@@ -145,7 +145,7 @@ Platform::Sigma0 *Platform::sigma0()
 
 Platform::Core_pager::Core_pager(Platform_pd *core_pd)
 :
-	Platform_thread("core.pager"), Pager_object(0)
+	Platform_thread("core.pager"), Pager_object(0, 0)
 {
 	Platform_thread::pager(sigma0());
 
diff --git a/base-foc/src/core/include/platform_thread.h b/base-foc/src/core/include/platform_thread.h
index 36564f631..273d4ad00 100644
--- a/base-foc/src/core/include/platform_thread.h
+++ b/base-foc/src/core/include/platform_thread.h
@@ -138,6 +138,11 @@ namespace Genode {
 			 */
 			void affinity(unsigned cpu);
 
+			/**
+			 * Get the executing CPU for this thread
+			 */
+			unsigned affinity();
+
 			/**
 			 * Return the address space to which the thread is bound
 			 */
diff --git a/base-foc/src/core/platform.cc b/base-foc/src/core/platform.cc
index 1522f5660..2e2db6d98 100644
--- a/base-foc/src/core/platform.cc
+++ b/base-foc/src/core/platform.cc
@@ -121,7 +121,7 @@ static void _core_pager_loop()
 }
 
 
-Platform::Sigma0::Sigma0(Cap_index* i) : Pager_object(0)
+Platform::Sigma0::Sigma0(Cap_index* i) : Pager_object(0, 0)
 {
 	/*
 	 * We use the Pager_object here in a slightly different manner,
@@ -132,7 +132,7 @@ Platform::Sigma0::Sigma0(Cap_index* i) : Pager_object(0)
 
 
 Platform::Core_pager::Core_pager(Platform_pd *core_pd, Sigma0 *sigma0)
-: Platform_thread("core.pager"), Pager_object(0)
+: Platform_thread("core.pager"), Pager_object(0, 0)
 {
 	Platform_thread::pager(sigma0);
 
diff --git a/base-foc/src/core/platform_thread.cc b/base-foc/src/core/platform_thread.cc
index a92620422..6e793b66f 100644
--- a/base-foc/src/core/platform_thread.cc
+++ b/base-foc/src/core/platform_thread.cc
@@ -209,6 +209,13 @@ void Platform_thread::affinity(unsigned cpu)
 }
 
 
+unsigned Platform_thread::affinity()
+{
+	PERR("'%s' not yet implemented", __PRETTY_FUNCTION__);
+	return 0;
+}
+
+
 void Platform_thread::_create_thread()
 {
 	l4_msgtag_t tag = l4_factory_create_thread(L4_BASE_FACTORY_CAP,
diff --git a/base-hw/src/core/include/platform_thread.h b/base-hw/src/core/include/platform_thread.h
index 13fcd96a0..a8246052e 100644
--- a/base-hw/src/core/include/platform_thread.h
+++ b/base-hw/src/core/include/platform_thread.h
@@ -154,6 +154,16 @@ namespace Genode {
 			void affinity(unsigned cpu) {
 				kernel_log() << __PRETTY_FUNCTION__ << ": not implemented\n"; };
 
+			/**
+			 * Get the executing CPU for this thread
+			 */
+			unsigned affinity()
+			{
+				kernel_log() << __PRETTY_FUNCTION__ << ": not implemented\n";
+				return 0;
+			};
+
+
 			/**
 			 * Return the address space to which the thread is bound
 			 */
diff --git a/base-nova/include/base/pager.h b/base-nova/include/base/pager.h
index 1ee6894ff..f589306f3 100644
--- a/base-nova/include/base/pager.h
+++ b/base-nova/include/base/pager.h
@@ -81,7 +81,7 @@ namespace Genode {
 			static Nova::Utcb * _check_handler(Thread_base *&, Pager_object *&);
 		public:
 
-			Pager_object(unsigned long badge);
+			Pager_object(unsigned long badge, unsigned affinity);
 
 			virtual ~Pager_object();
 
diff --git a/base-nova/src/base/pager/pager.cc b/base-nova/src/base/pager/pager.cc
index a642e9779..59c486e52 100644
--- a/base-nova/src/base/pager/pager.cc
+++ b/base-nova/src/base/pager/pager.cc
@@ -257,7 +257,7 @@ static uint8_t create_portal(addr_t pt, addr_t pd, addr_t ec, Mtd mtd,
 	return res;	
 }
 
-Pager_object::Pager_object(unsigned long badge)
+Pager_object::Pager_object(unsigned long badge, unsigned affinity)
 : Thread_base("pager:", PF_HANDLER_STACK_SIZE), _badge(badge)
 {
 	class Create_exception_pt_failed { };
diff --git a/base-nova/src/core/include/platform_thread.h b/base-nova/src/core/include/platform_thread.h
index 9572bf737..5a1212409 100644
--- a/base-nova/src/core/include/platform_thread.h
+++ b/base-nova/src/core/include/platform_thread.h
@@ -131,6 +131,11 @@ namespace Genode {
 			 */
 			void affinity(unsigned cpu);
 
+			/**
+			 * Get the executing CPU for this thread
+			 */
+			unsigned affinity();
+
 			/**
 			 * Get thread name
 			 */
diff --git a/base-nova/src/core/platform_thread.cc b/base-nova/src/core/platform_thread.cc
index ac356b470..1f93bc65c 100644
--- a/base-nova/src/core/platform_thread.cc
+++ b/base-nova/src/core/platform_thread.cc
@@ -46,6 +46,9 @@ void Platform_thread::affinity(unsigned int cpu_no)
 }
 
 
+unsigned Platform_thread::affinity() { return _cpu_no; }
+
+
 int Platform_thread::start(void *ip, void *sp)
 {
 	using namespace Nova;
@@ -323,7 +326,7 @@ Weak_ptr<Address_space> Platform_thread::address_space()
 Platform_thread::Platform_thread(const char *name, unsigned, int thread_id)
 :
 	_pd(0), _pager(0), _id_base(cap_selector_allocator()->alloc(1)),
-	_sel_exc_base(Native_thread::INVALID_INDEX), _cpu_no(0),
+	_sel_exc_base(Native_thread::INVALID_INDEX), _cpu_no(0), //XXX find out boot CPU
 	_is_main_thread(false), _is_vcpu(false)
 {
 	strncpy(_name, name, sizeof(_name));
diff --git a/base-okl4/src/core/include/platform_thread.h b/base-okl4/src/core/include/platform_thread.h
index 44404cdbc..971486f03 100644
--- a/base-okl4/src/core/include/platform_thread.h
+++ b/base-okl4/src/core/include/platform_thread.h
@@ -142,6 +142,11 @@ namespace Genode {
 			 */
 			void affinity(unsigned cpu);
 
+			/**
+			 * Request the affinity of this thread
+			 */
+			unsigned affinity();
+
 
 			/*****************************
 			 ** OKL4-specific Accessors **
diff --git a/base-okl4/src/core/platform_thread.cc b/base-okl4/src/core/platform_thread.cc
index b88e74475..1678a489b 100644
--- a/base-okl4/src/core/platform_thread.cc
+++ b/base-okl4/src/core/platform_thread.cc
@@ -38,7 +38,14 @@ using namespace Okl4;
 
 void Platform_thread::affinity(unsigned int cpu_no)
 {
-	PERR("not yet implemented");
+	PERR("'%s' not yet implemented", __PRETTY_FUNCTION__);
+}
+
+
+unsigned Platform_thread::affinity()
+{
+	PERR("'%s' not yet implemented", __PRETTY_FUNCTION__);
+	return 0;
 }
 
 
diff --git a/base-pistachio/src/core/include/platform.h b/base-pistachio/src/core/include/platform.h
index f96db5e2e..69ef20fba 100644
--- a/base-pistachio/src/core/include/platform.h
+++ b/base-pistachio/src/core/include/platform.h
@@ -150,6 +150,8 @@ namespace Genode {
 			Rom_fs          *rom_fs()         { return &_rom_fs; }
 
 			void wait_for_exit();
+			unsigned num_cpus() const {
+				return L4_NumProcessors(Pistachio::get_kip()); }
 	};
 }
 
diff --git a/base-pistachio/src/core/include/platform_thread.h b/base-pistachio/src/core/include/platform_thread.h
index c47a06044..91146994e 100644
--- a/base-pistachio/src/core/include/platform_thread.h
+++ b/base-pistachio/src/core/include/platform_thread.h
@@ -142,6 +142,11 @@ namespace Genode {
 			 */
 			void affinity(unsigned cpu);
 
+			/**
+			 * Request the affinity of this thread
+			 */
+			unsigned affinity();
+
 
 			/**********************************
 			 ** Pistachio-specific Accessors **
diff --git a/base-pistachio/src/core/platform.cc b/base-pistachio/src/core/platform.cc
index 5af8ab1b3..ccb0889d6 100644
--- a/base-pistachio/src/core/platform.cc
+++ b/base-pistachio/src/core/platform.cc
@@ -199,7 +199,7 @@ static void _core_pager_loop()
 }
 
 
-Platform::Sigma0::Sigma0() : Pager_object(0)
+Platform::Sigma0::Sigma0() : Pager_object(0, 0)
 {
 	cap(Native_capability(Pistachio::get_sigma0(), 0));
 }
@@ -214,7 +214,7 @@ Platform::Sigma0 *Platform::sigma0()
 
 Platform::Core_pager::Core_pager(Platform_pd *core_pd)
 :
-	Platform_thread("core.pager"), Pager_object(0)
+	Platform_thread("core.pager"), Pager_object(0, 0)
 {
 	Platform_thread::pager(sigma0());
 
diff --git a/base-pistachio/src/core/platform_thread.cc b/base-pistachio/src/core/platform_thread.cc
index 5c71107e1..47e69f453 100644
--- a/base-pistachio/src/core/platform_thread.cc
+++ b/base-pistachio/src/core/platform_thread.cc
@@ -51,6 +51,13 @@ void Platform_thread::affinity(unsigned int cpu_no)
 }
 
 
+unsigned Platform_thread::affinity()
+{
+	PERR("'%s' not yet implemented", __PRETTY_FUNCTION__);
+	return 0;
+}
+
+
 int Platform_thread::start(void *ip, void *sp, unsigned int cpu_no)
 {
 	L4_ThreadId_t thread = _l4_thread_id;
diff --git a/base/include/base/pager.h b/base/include/base/pager.h
index 187583b4c..c51baebec 100644
--- a/base/include/base/pager.h
+++ b/base/include/base/pager.h
@@ -58,7 +58,7 @@ namespace Genode {
 			 */
 			Thread_state state;
 
-			Pager_object(unsigned long badge) : _badge(badge) { }
+			Pager_object(unsigned long badge, unsigned affinity) : _badge(badge) { }
 			virtual ~Pager_object() { }
 
 			unsigned long badge() const { return _badge; }
diff --git a/base/src/core/include/rm_session_component.h b/base/src/core/include/rm_session_component.h
index c54c358ab..732afd9cf 100644
--- a/base/src/core/include/rm_session_component.h
+++ b/base/src/core/include/rm_session_component.h
@@ -197,12 +197,14 @@ namespace Genode {
 			 * \param session  RM session to which the client belongs
 			 * \param badge    pager-object badge used of identifying the client
 			 *                 when a page-fault occurs
+			 * \param affinity cpu affinity
 			 */
 			Rm_client(Rm_session_component *session, unsigned long badge,
-			          Weak_ptr<Address_space> &address_space)
+			          Weak_ptr<Address_space> &address_space,
+			          unsigned affinity)
 			:
-				Pager_object(badge), Rm_member(session), Rm_faulter(this),
-				_address_space(address_space) { }
+				Pager_object(badge, affinity), Rm_member(session),
+				Rm_faulter(this), _address_space(address_space) { }
 
 			int pager(Ipc_pager &pager);
 
diff --git a/base/src/core/rm_session_component.cc b/base/src/core/rm_session_component.cc
index 6c0054b0f..a3419a328 100644
--- a/base/src/core/rm_session_component.cc
+++ b/base/src/core/rm_session_component.cc
@@ -605,6 +605,7 @@ void Rm_session_component::detach(Local_addr local_addr)
 Pager_capability Rm_session_component::add_client(Thread_capability thread)
 {
 	unsigned long badge;
+	unsigned affinity;
 	Weak_ptr<Address_space> address_space;
 
 	{
@@ -615,6 +616,8 @@ Pager_capability Rm_session_component::add_client(Thread_capability thread)
 
 		/* determine identification of client when faulting */
 		badge = cpu_thread->platform_thread()->pager_object_badge();
+		/* determine cpu affinity of client thread */
+		affinity = cpu_thread->platform_thread()->affinity();
 
 		address_space = cpu_thread->platform_thread()->address_space();
 		if (!Locked_ptr<Address_space>(address_space).is_valid())
@@ -625,7 +628,7 @@ Pager_capability Rm_session_component::add_client(Thread_capability thread)
 	Lock::Guard lock_guard(_lock);
 
 	Rm_client *cl;
-	try { cl = new(&_client_slab) Rm_client(this, badge, address_space); }
+	try { cl = new(&_client_slab) Rm_client(this, badge, address_space, affinity); }
 	catch (Allocator::Out_of_memory) { throw Out_of_metadata(); }
 	catch (Cpu_session::Thread_creation_failed) { throw Out_of_metadata(); }
 	catch (Thread_base::Stack_alloc_failed) { throw Out_of_metadata(); }