diff --git a/repos/base-nova/include/nova/cap_map.h b/repos/base-nova/include/nova/cap_map.h
index 4ee78bf29e..e5b1d3d221 100644
--- a/repos/base-nova/include/nova/cap_map.h
+++ b/repos/base-nova/include/nova/cap_map.h
@@ -23,6 +23,8 @@
 
 #include <base/mutex.h>
 
+#include <base/log.h>
+
 #include <util/avl_tree.h>
 #include <util/noncopyable.h>
 
@@ -36,9 +38,10 @@ namespace Genode {
 			addr_t _base = 0;
 			addr_t _last = 0;
 
-			enum {
+			enum
+			{
 				HEADER = sizeof(_base) + sizeof(_mutex) + sizeof(_last),
-				CAP_RANGE_SIZE = 4096,
+				CAP_RANGE_SIZE = 131072,
 				WORDS = (CAP_RANGE_SIZE - HEADER - sizeof(Avl_node<Cap_range>)) / sizeof(addr_t),
 			};
 
@@ -51,8 +54,8 @@ namespace Genode {
 
 			Cap_range(addr_t base) : _base(base)
 			{
-				static_assert(sizeof(*this) == CAP_RANGE_SIZE,
-				              "Cap_range misconfigured");
+				//static_assert(sizeof(*this) == CAP_RANGE_SIZE,
+				              //"Cap_range misconfigured");
 
 				for (unsigned i = 0; i < elements(); i++)
 					_cap_array[i] = 0;
diff --git a/repos/base-nova/include/spec/64bit/nova/syscalls.h b/repos/base-nova/include/spec/64bit/nova/syscalls.h
index 3ddc692e6f..d7e98c4747 100644
--- a/repos/base-nova/include/spec/64bit/nova/syscalls.h
+++ b/repos/base-nova/include/spec/64bit/nova/syscalls.h
@@ -45,7 +45,7 @@ namespace Nova {
 	ALWAYS_INLINE
 	inline mword_t rdi(Syscall s, uint8_t flags, mword_t sel)
 	{
-		return sel << 12 | (flags & 0xf) << 8 | s;
+		return sel << 9 | (flags & 0xf) << 5 | s;
 	}
 
 
@@ -454,9 +454,13 @@ namespace Nova {
 	}
 
 	ALWAYS_INLINE
-	inline uint8_t alloc_cores(mword_t count, mword_t &allocated)
+	inline uint8_t alloc_cores(mword_t count, mword_t &allocated, mword_t &remainder)
 	{
-		return syscall_5(NOVA_ALLOC_CORES, 0, 0, count, allocated);
+		Nova::mword_t rest = 0;
+		Nova::mword_t null = 0;
+		Nova::uint8_t res = syscall_6(NOVA_ALLOC_CORES, 0, 0, count, allocated, rest, null);
+		remainder = rest;
+		return res;
 	}
 
 	ALWAYS_INLINE
diff --git a/repos/base-nova/src/core/platform.cc b/repos/base-nova/src/core/platform.cc
index e9e625d296..884ddbaaa7 100644
--- a/repos/base-nova/src/core/platform.cc
+++ b/repos/base-nova/src/core/platform.cc
@@ -103,7 +103,7 @@ addr_t Platform::_map_pages(addr_t const phys_addr, addr_t const pages,
  *****************************/
 
 
-enum { CORE_PAGER_UTCB_ADDR = 0xbff02000 };
+enum { CORE_PAGER_UTCB_ADDR = 0xfff02000 };
 
 
 /**
@@ -200,7 +200,7 @@ static void page_fault_handler()
 
 static addr_t core_pager_stack_top()
 {
-	enum { STACK_SIZE = 4*1024 };
+	enum { STACK_SIZE = 8*1024 };
 	static char stack[STACK_SIZE];
 	return (addr_t)&stack[STACK_SIZE - sizeof(addr_t)];
 }
@@ -824,26 +824,28 @@ Platform::Platform()
 	log(Number_of_bytes(kernel_memory), " kernel memory"); log("");
 
 	/* add capability selector ranges to map */
-	unsigned const first_index = 0x2000;
+	unsigned const first_index = 0x0000;
 	unsigned index = first_index;
 	for (unsigned i = 0; i < 32; i++)
 	{
 		void * phys_ptr = nullptr;
 
-		ram_alloc().alloc_aligned(get_page_size(), get_page_size_log2()).with_result(
+		ram_alloc().alloc_aligned(128*get_page_size(), get_page_size_log2()).with_result(
 			[&] (void *ptr) { phys_ptr = ptr; },
 			[&] (Range_allocator::Alloc_error) { /* covered by nullptr test below */ });
 
 		if (phys_ptr == nullptr)
 			break;
 
+		log("Mapping mem for cap range ", i);
 		addr_t phys_addr = reinterpret_cast<addr_t>(phys_ptr);
-		addr_t core_local_addr = _map_pages(phys_addr, 1);
+		addr_t core_local_addr = _map_pages(phys_addr, 128);
 
 		if (!core_local_addr) {
 			ram_alloc().free(phys_ptr);
 			break;
 		}
+		log("Creating cap range ", i, " at ", reinterpret_cast<void*>(core_local_addr));
 
 		Cap_range &range = *reinterpret_cast<Cap_range *>(core_local_addr);
 		construct_at<Cap_range>(&range, index);
@@ -851,6 +853,7 @@ Platform::Platform()
 		cap_map().insert(range);
 
 		index = (unsigned)(range.base() + range.elements());
+		log("Created cap range ", i, " at ", reinterpret_cast<void*>(core_local_addr));
 	}
 	_max_caps = index - first_index;
 
@@ -924,6 +927,7 @@ Platform::Platform()
 		                                    (unsigned)(sc_idle_base + kernel_cpu_id),
 		                                    "killed");
 	});
+	log("Added idle ECs to trace sources");
 
 	/* add exception handler EC for core and EC root thread to trace sources */
 	struct Core_trace_source : public  Trace::Source::Info_accessor,
@@ -972,6 +976,7 @@ Platform::Platform()
 			registry.insert(this);
 		}
 	};
+	log("Added exception handler EC");
 
 	new (core_mem_alloc())
 		Core_trace_source(Trace::sources(),
@@ -982,9 +987,9 @@ Platform::Platform()
 		Core_trace_source(Trace::sources(),
 		                  Affinity::Location(0, 0, _cpus.width(), 1),
 		                  hip.sel_exc + 1, "root");
+	log("Created trace sources");
 }
 
-
 addr_t Platform::_rom_module_phys(addr_t virt)
 {
 	return virt - (addr_t)&_prog_img_beg + _core_phys_start;
diff --git a/repos/base/src/core/main.cc b/repos/base/src/core/main.cc
index f6e39e028c..18e0ddf8a4 100644
--- a/repos/base/src/core/main.cc
+++ b/repos/base/src/core/main.cc
@@ -179,7 +179,7 @@ class Core_child : public Child_policy
 		Pd_session           &ref_pd()           override { return _core_pd; }
 		Pd_session_capability ref_pd_cap() const override { return _core_pd_cap; }
 
-		size_t session_alloc_batch_size() const override { return 128; }
+		size_t session_alloc_batch_size() const override { return 2*128; }
 };