diff -r 68521d709355 xen/arch/x86/hvm/vlapic.c
--- a/xen/arch/x86/hvm/vlapic.c	Tue Sep 11 15:33:54 2007 -0400
+++ b/xen/arch/x86/hvm/vlapic.c	Tue Sep 11 15:33:54 2007 -0400
@@ -962,6 +962,11 @@ void vlapic_destroy(struct vcpu *v)
     free_domheap_page(vlapic->regs_page);
 }
 
+int is_lvtt_vector(struct vcpu *v, int vector)
+{
+    return (vector == vlapic_lvt_vector(vcpu_vlapic(v), APIC_LVTT));
+}
+
 int is_lvtt(struct vcpu *v, int vector)
 {
     return vcpu_vlapic(v)->pt.enabled &&
diff -r 68521d709355 xen/arch/x86/hvm/vpt.c
--- a/xen/arch/x86/hvm/vpt.c	Tue Sep 11 15:33:54 2007 -0400
+++ b/xen/arch/x86/hvm/vpt.c	Tue Sep 11 15:33:54 2007 -0400
@@ -277,6 +277,13 @@ void create_periodic_time(
     pt->period_cycles = (u64)period * cpu_khz / 1000000L;
     pt->one_shot = one_shot;
     pt->scheduled = NOW() + period;
+    if (is_lvtt_vector(v, irq))
+    {
+        /* Try to offset local APIC ticks from timer ticks.  Otherwise, guests
+           using the local APIC for process accounting can see long sequences
+           of process ticks incorrectly charged to interrupt processing. */
+        pt->scheduled += (period >> 1);
+    }
     pt->cb = cb;
     pt->priv = data;
 
diff -r 68521d709355 xen/include/asm-x86/hvm/vlapic.h
--- a/xen/include/asm-x86/hvm/vlapic.h	Tue Sep 11 15:33:54 2007 -0400
+++ b/xen/include/asm-x86/hvm/vlapic.h	Tue Sep 11 15:33:54 2007 -0400
@@ -92,6 +92,7 @@ struct vlapic *apic_round_robin(
 
 int vlapic_match_logical_addr(struct vlapic *vlapic, uint8_t mda);
 
+int is_lvtt_vector(struct vcpu *v, int vector);
 int is_lvtt(struct vcpu *v, int vector);
 int is_lvtt_enabled(struct vcpu *v);