diff -urN linux-2.4.20/arch/i386/mm/init.c linux/arch/i386/mm/init.c
--- linux-2.4.20/arch/i386/mm/init.c	2003-02-20 16:12:34.000000000 +0100
+++ linux/arch/i386/mm/init.c	2003-02-20 16:20:20.000000000 +0100
@@ -282,14 +282,35 @@
 	flush_tlb_all();
 }
 
+#if CONFIG_HIGHMEM64G
+#define MIN_ZONE_DMA_PAGES 1024
+#else
+#define MIN_ZONE_DMA_PAGES 4096
+#endif
+
 static void __init zone_sizes_init(void)
 {
 	unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0};
-	unsigned int max_dma, high, low;
+	unsigned int max_dma, ratio_maxdma, high, low;
 
 	max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
 	low = max_low_pfn;
 	high = highend_pfn;
+	
+	/*
+	 * Make the DMA zone 5% of memory, with a minimum of 4Mb
+	 * and a maximum of 16Mb.
+	 */
+	#if MAX_ORDER != 10
+	#error fix this
+	#endif
+	ratio_maxdma = (highend_pfn / 20) & ~((1 << MAX_ORDER)-1); 
+	if (ratio_maxdma > max_dma)
+		ratio_maxdma = max_dma;
+	if (ratio_maxdma < MIN_ZONE_DMA_PAGES)
+		ratio_maxdma = MIN_ZONE_DMA_PAGES;
+		
+	max_dma = ratio_maxdma;
 
 	if (low < max_dma)
 		zones_size[ZONE_DMA] = low;
diff -urN linux-2.4.20/mm/page_alloc.c linux/mm/page_alloc.c
--- linux-2.4.20/mm/page_alloc.c	2003-02-20 16:12:29.000000000 +0100
+++ linux/mm/page_alloc.c	2003-02-20 16:22:54.000000000 +0100
@@ -38,11 +38,19 @@
 EXPORT_SYMBOL(zone_table);
 
 static char *zone_names[MAX_NR_ZONES] = { "DMA", "Normal", "HighMem" };
+#ifdef CONFIG_HIGHMEM64G
+static int zone_balance_ratio[MAX_NR_ZONES] __initdata = { 4097, 128, 128, };
+static int zone_balance_min[MAX_NR_ZONES] __initdata = { 0 , 20, 20, };
+static int zone_balance_max[MAX_NR_ZONES] __initdata = { 0 , 255, 255, };
+static int zone_extrafree_ratio[MAX_NR_ZONES] __initdata = { 4097, 512, 0, };
+static int zone_extrafree_max[MAX_NR_ZONES] __initdata = { 0 , 1024, 0, };
+#else
 static int zone_balance_ratio[MAX_NR_ZONES] __initdata = { 128, 128, 128, };
 static int zone_balance_min[MAX_NR_ZONES] __initdata = { 20 , 20, 20, };
 static int zone_balance_max[MAX_NR_ZONES] __initdata = { 255 , 255, 255, };
 static int zone_extrafree_ratio[MAX_NR_ZONES] __initdata = { 128, 512, 0, };
 static int zone_extrafree_max[MAX_NR_ZONES] __initdata = { 1024 , 1024, 0, };
+#endif
 
 /*
  * Temporary debugging check.
@@ -843,6 +851,9 @@
 				zone = pgdat->node_zones + ZONE_NORMAL;
 				if (zone->size)
 					zonelist->zones[j++] = zone;
+#ifdef CONFIG_HIGHMEM64G					
+				break;
+#endif				
 			case ZONE_DMA:
 				zone = pgdat->node_zones + ZONE_DMA;
 				if (zone->size)
diff -urN linux-2.4.20/mm/vmscan.c linux/mm/vmscan.c
--- linux-2.4.20/mm/vmscan.c	2003-02-20 16:12:33.000000000 +0100
+++ linux/mm/vmscan.c	2003-02-20 16:16:12.000000000 +0100
@@ -945,9 +945,16 @@
 	 */
 	rebalance_inactive(gfp_mask, 5);
 
-	for_each_zone(zone)
-		while (need_rebalance_dirty(zone))
+	for_each_zone(zone) {
+		int maxloops;
+		
+		maxloops = zone->active_anon_pages +
+			   zone->active_cache_pages +
+			   zone->inactive_dirty_pages;
+		maxloops = maxloops / (16 * BATCH_WORK_AMOUNT) + 1;
+		while (need_rebalance_dirty(zone) && maxloops--)
 			rebalance_dirty_zone(zone,  16 * BATCH_WORK_AMOUNT,  gfp_mask);
+	}
 
 	for_each_zone(zone)
 		if (free_high(zone)>0)
@@ -1201,12 +1208,12 @@
  * no VM pressure at all it shouldn't age stuff either otherwise everything
  * ends up at the maximum age. 
  */
-#define MAX_AGING_INTERVAL ((unsigned long)5*HZ)
-#define MIN_AGING_INTERVAL ((unsigned long)HZ/2)
-int kscand(void *unused)
+#define MAX_AGING_INTERVAL ((unsigned long)25*HZ)
+#define MIN_AGING_INTERVAL ((unsigned long)HZ+1)
+int kscand(void *param_zone)
 {
 	struct task_struct *tsk = current;
-	struct zone_struct * zone;
+	struct zone_struct * zone = (struct zone_struct*)param_zone;
 	unsigned long pause = MAX_AGING_INTERVAL;
 	int total_needscan = 0;
 	int age_faster = 0;
@@ -1214,59 +1221,56 @@
 	int age;
 
 	daemonize();
-	strcpy(tsk->comm, "kscand");
+	snprintf(tsk->comm, 20, "kscand/%s",zone->name);
 	sigfillset(&tsk->blocked);
 	
 	for (;;) {
 		set_current_state(TASK_INTERRUPTIBLE);
 		schedule_timeout(pause);	
-		
+	
 		if (signal_pending(current)) {
 			flush_signals(current);
 			printk(KERN_CRIT "kscand received a signal and is confused\n");
 		}
-		for_each_zone(zone) {
-			if (need_active_anon_scan(zone)) {
-				for (age = 0; age < MAX_AGE; age++)  {
-					scan_active_list(zone, age, 1);
-					if (current->need_resched)
-						schedule();
-				}
+		
+		if (need_active_anon_scan(zone)) {
+			for (age = 0; age < MAX_AGE; age++)  {
+				scan_active_list(zone, age, 1);
+				if (current->need_resched)
+					schedule();
 			}
+		}
 
-			if (need_active_cache_scan(zone)) {
-				for (age = 0; age < MAX_AGE; age++)  {
-					scan_active_list(zone, age, 0);
-					if (current->need_resched)
-						schedule();
-				}
+		if (need_active_cache_scan(zone)) {
+			for (age = 0; age < MAX_AGE; age++)  {
+				scan_active_list(zone, age, 0);
+				if (current->need_resched)
+					schedule();
 			}
-
-			/* Check if we've been aging quickly enough */
-			if (zone->need_scan >= 2)
-				age_faster++;
-			total_needscan += zone->need_scan;
-			zone->need_scan = 0;
-			num_zones++;
 		}
-		if (age_faster)
+
+		/* Check if we've been scanning quickly enough 
+		 * If we had two or more age events, we need to scan faster,
+		 * but if there were none, we can try to go to a lower frequency again
+		 */
+		if (zone->need_scan >= 2)
 			pause = max(pause / 2, MIN_AGING_INTERVAL);
-		else if (total_needscan < num_zones)
+		else if (zone->need_scan == 0)
 			pause = min(pause + pause / 2, MAX_AGING_INTERVAL);
 
-		total_needscan = 0;
-		age_faster = 0;
-		num_zones = 0;
+		zone->need_scan = 0;
 	}
 }
 
 
 static int __init kswapd_init(void)
 {
+	struct zone_struct * zone;
 	printk("Starting kswapd\n");
 	swap_setup();
 	kernel_thread(kswapd, NULL, CLONE_KERNEL);
-	kernel_thread(kscand, NULL, CLONE_KERNEL);
+	for_each_zone(zone) 
+		kernel_thread(kscand, zone, CLONE_KERNEL);
 	return 0;
 }