diff -aru ../xen-2.0.7-orig/linux-2.6.11-xen-sparse/arch/xen/i386/kernel/time.c linux-2.6.11-xen-sparse/arch/xen/i386/kernel/time.c
--- ../xen-2.0.7-orig/linux-2.6.11-xen-sparse/arch/xen/i386/kernel/time.c	2005-08-03 16:57:57.000000000 -0700
+++ linux-2.6.11-xen-sparse/arch/xen/i386/kernel/time.c	2005-09-22 18:19:36.000000000 -0700
@@ -96,6 +96,11 @@
 static struct timeval shadow_tv;
 extern u64 processed_system_time;
 
+/* DG: local copy of the tdf, only for guests */
+#ifndef CONFIG_XEN_PRIVILEGED_GUEST
+u32 time_dilation_factor;
+#endif
+
 /*
  * We use this to ensure that gettimeofday() is monotonically increasing. We
  * only break this guarantee if the wall clock jumps backwards "a long way".
@@ -165,6 +170,9 @@
 		shadow_tv.tv_usec   = s->wc_usec;
 		shadow_tsc_stamp    = (u32)s->tsc_timestamp;
 		shadow_system_time  = s->system_time;
+#ifndef CONFIG_XEN_PRIVILEGED_GUEST
+        time_dilation_factor = s->time_dilation_factor;
+#endif
 		rmb();
 	}
 	while (shadow_time_version != s->time_version1);
@@ -381,6 +389,21 @@
 	s64 delta, nsec;
 	long sec_diff, wtm_nsec;
 
+    /* TDF: new variables */
+    u32 sync_time, warp_time;
+
+#ifndef CONFIG_XEN_PRIVILEGED_GUEST
+    /* if we have a TDF > 1, then do aggressive time syncing
+     * basically on every timer interrupt */
+    if(time_dilation_factor > 1)
+        sync_time = 0;
+
+    /* if we have a TDF > 1, then we need to scale the warp time
+     * appropriately */
+    if(time_dilation_factor > 1)
+        warp_time /= time_dilation_factor;
+#endif
+
 	do {
 		__get_time_values_from_xen();
 
@@ -388,6 +411,16 @@
 			      ((s64)cur_timer->get_offset() * 
 			       (s64)NSEC_PER_USEC) -
 			      processed_system_time);
+#ifndef CONFIG_XEN_PRIVILEGED_GUEST
+        /* ideally, this should never happen */
+        if(delta < 0)
+        {
+            /* we some how ran ahead, re-sync */
+            shadow_system_time = processed_system_time;
+            /* reassign delta, always +ve */
+            delta = (cur_timer->get_offset() * NSEC_PER_USEC);
+        }
+#endif
 	}
 	while (!TIME_VALUES_UP_TO_DATE);
 
@@ -418,7 +451,7 @@
 	 */
 	if (!INDEPENDENT_WALLCLOCK() &&
 	    ((time_status & STA_UNSYNC) != 0) &&
-	    (xtime.tv_sec > (last_update_from_xen + 60))) {
+	    (xtime.tv_sec > (last_update_from_xen + sync_time))) {
 		/* Adjust shadow for jiffies that haven't updated xtime yet. */
 		shadow_tv.tv_usec -= 
 			(jiffies - wall_jiffies) * (USEC_PER_SEC / HZ);
@@ -432,7 +465,7 @@
 		if (unlikely(abs(sec_diff) > 1) ||
 		    unlikely(((sec_diff * USEC_PER_SEC) +
 			      (xtime.tv_nsec / NSEC_PER_USEC) -
-			      shadow_tv.tv_usec) > 500000)) {
+			      shadow_tv.tv_usec) > warp_time)) {
 #ifdef CONFIG_XEN_PRIVILEGED_GUEST
 			last_rtc_update = last_update_to_xen = 0;
 #endif
@@ -672,6 +705,7 @@
 {
 	unsigned int cpu = smp_processor_id();
 	unsigned long j;
+    u64 alarm = 0;
 
 	/* s390 does this /before/ checking rcu_pending(). We copy them. */
 	cpu_set(cpu, nohz_cpu_mask);
@@ -684,7 +718,14 @@
 		j = next_timer_interrupt();
 	}
 
-	BUG_ON(HYPERVISOR_set_timer_op(__jiffies_to_st(j)) != 0);
+#ifdef CONFIG_XEN_PRIVILEGED_GUEST
+    alarm = __jiffies_to_st(j);
+#else
+    alarm = time_dilation_factor * __jiffies_to_st(j);
+#endif
+    
+	/*BUG_ON(HYPERVISOR_set_timer_op(__jiffies_to_st(j)) != 0);*/
+	BUG_ON(HYPERVISOR_set_timer_op(alarm) != 0);
 }
 
 void start_hz_timer(void)
diff -aru ../xen-2.0.7-orig/linux-2.6.11-xen-sparse/include/asm-xen/asm-i386/param.h linux-2.6.11-xen-sparse/include/asm-xen/asm-i386/param.h
--- ../xen-2.0.7-orig/linux-2.6.11-xen-sparse/include/asm-xen/asm-i386/param.h	2005-08-03 16:57:57.000000000 -0700
+++ linux-2.6.11-xen-sparse/include/asm-xen/asm-i386/param.h	2005-09-22 18:19:53.000000000 -0700
@@ -2,7 +2,8 @@
 #define _ASMi386_PARAM_H
 
 #ifdef __KERNEL__
-# define HZ		100		/* Internal kernel timer frequency */
+/* DG: Xen originally used HZ = 100 for the guests */
+# define HZ		1000		/* Internal kernel timer frequency */
 # define USER_HZ	100		/* .. some user interfaces are in "ticks" */
 # define CLOCKS_PER_SEC		(USER_HZ)	/* like times() */
 #endif