diff --git a/src/system/kernel/sem.c b/src/system/kernel/sem.c
index 2dbc0b71a1..de508e8d3a 100644
--- a/src/system/kernel/sem.c
+++ b/src/system/kernel/sem.c
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2007, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
+ * Copyright 2002-2008, Axel Dörfler, axeld@pinc-software.de. All rights reserved.
  * Distributed under the terms of the MIT License.
  *
  * Copyright 2001, Travis Geiselbrecht. All rights reserved.
@@ -67,7 +67,7 @@ struct sem_entry {
 	} u;
 };
 
-static const int32 kMaxSemaphores = 65536;
+static const int32 kMaxSemaphores = 131072;
 static int32 sMaxSems = 4096;
 	// Final value is computed based on the amount of available memory
 static int32 sUsedSems = 0;
@@ -350,7 +350,8 @@ sem_init(kernel_args *args)
 	// compute maximal number of semaphores depending on the available memory
 	// 128 MB -> 16384 semaphores, 448 kB fixed array size
 	// 256 MB -> 32768, 896 kB
-	// 512 MB and more -> 1.75 MB
+	// 512 MB -> 65536, 1.75 MB
+	// 1024 MB and more -> 131072, 3.5 MB
 	i = vm_page_num_pages() / 2;
 	while (sMaxSems < i && sMaxSems < kMaxSemaphores)
 		sMaxSems <<= 1;
@@ -399,6 +400,9 @@ create_sem_etc(int32 count, const char *name, team_id owner)
 	if (sSemsActive == false)
 		return B_NO_MORE_SEMS;
 
+#if 0
+	// TODO: the code below might cause unwanted deadlocks,
+	// we need an asynchronously running low resource handler.
 	if (sUsedSems == sMaxSems) {
 		// The vnode cache may have collected lots of semaphores.
 		// Freeing some unused vnodes should improve our situation.
@@ -410,6 +414,7 @@ create_sem_etc(int32 count, const char *name, team_id owner)
 		// try again with more enthusiasm
 		vfs_free_unused_vnodes(B_LOW_MEMORY_CRITICAL);
 	}
+#endif
 	if (sUsedSems == sMaxSems)
 		return B_NO_MORE_SEMS;
 
diff --git a/src/system/kernel/vm/vm.cpp b/src/system/kernel/vm/vm.cpp
index 3d8dd33b88..204f2115b5 100644
--- a/src/system/kernel/vm/vm.cpp
+++ b/src/system/kernel/vm/vm.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2007, Axel Dörfler, axeld@pinc-software.de.
+ * Copyright 2002-2008, Axel Dörfler, axeld@pinc-software.de.
  * Distributed under the terms of the MIT License.
  *
  * Copyright 2001-2002, Travis Geiselbrecht. All rights reserved.
@@ -3468,6 +3468,8 @@ vm_init(kernel_args *args)
 		heapSize /= 4;
 	else if (sAvailableMemory < 200 * 1024 * 1024)
 		heapSize /= 2;
+	else if (sAvailableMemory >= 1024 * 1024 * 1024)
+		heapSize *= 2;
 
 	// map in the new heap and initialize it
 	addr_t heapBase = vm_allocate_early(args, heapSize, heapSize,
diff --git a/src/system/kernel/vm/vm_low_memory.cpp b/src/system/kernel/vm/vm_low_memory.cpp
index b3ff74ffe5..9a3c7aea28 100644
--- a/src/system/kernel/vm/vm_low_memory.cpp
+++ b/src/system/kernel/vm/vm_low_memory.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2005-2007, Axel Dörfler, axeld@pinc-software.de.
+ * Copyright 2005-2008, Axel Dörfler, axeld@pinc-software.de.
  * Distributed under the terms of the MIT License.
  */
 
@@ -14,6 +14,7 @@
 
 #include <elf.h>
 #include <lock.h>
+#include <sem.h>
 #include <util/AutoLock.h>
 #include <util/DoublyLinkedList.h>
 #include <vm_page.h>
@@ -74,13 +75,22 @@ compute_state(void)
 	sLastMeasurement = system_time();
 
 	uint32 freePages = vm_page_num_free_pages();
+
+	if (freePages > kNoteLimit) {
+		// TODO: work-around for a missing general low resource handler
+		if (sem_used_sems() * 6 > sem_max_sems() * 5)
+			return B_LOW_MEMORY_WARNING;
+		if (sem_used_sems() * 3 > sem_max_sems() * 2)
+			return B_LOW_MEMORY_NOTE;
+	}
+
 	if (freePages >= kNoteLimit)
 		return B_NO_LOW_MEMORY;
 
 	// specify low memory level
 	if (freePages < kCriticalLimit)
 		return B_LOW_MEMORY_CRITICAL;
-	else if (freePages < kWarnLimit)
+	if (freePages < kWarnLimit)
 		return B_LOW_MEMORY_WARNING;
 
 	return B_LOW_MEMORY_NOTE;