diff --git a/sys/src/9/pc64/trap.c b/sys/src/9/pc64/trap.c
--- a/sys/src/9/pc64/trap.c
+++ b/sys/src/9/pc64/trap.c
@@ -28,6 +28,7 @@ enum
 	Ntimevec = 20		/* number of time buckets for each intr */
 };
 ulong intrtimes[256][Ntimevec];
+ulong intrcount[256];
 
 void
 intrenable(int irq, void (*f)(Ureg*, void*), void* a, int tbdf, char *name)
@@ -153,6 +154,35 @@ irqallocread(Chan*, void *a, long n, vlo
 	return 0;
 }
 
+static long
+irqstatread(Chan*, void *a, long n, vlong offset)
+{
+	char buf[READSTR];
+	char *p, *e;
+	int i, vno;
+	ulong *t;
+	Vctl *v;
+
+	p = buf;
+	e = p+sizeof(buf);
+
+	for(vno = 0; vno < nelem(vctl); vno++){
+		if((v = vctl[vno]) == nil)
+			continue;
+
+		t = intrtimes[vno];
+
+		p = seprint(p, e, "%-3d %-15q %lud", vno, v->name, intrcount[vno]);
+
+		for(i = 0; i < Ntimevec; i++)
+			p = seprint(p, e, " %lud", t[i]);
+
+		p = strecpy(p, e, "\n");
+	}
+
+	return readstr(offset, a, n, buf);
+}
+
 void
 trapenable(int vno, void (*f)(Ureg*, void*), void* a, char *name)
 {
@@ -243,6 +273,7 @@ trapinit(void)
 	trapenable(Vector15, unexpected, 0, "unexpected");
 	nmienable();
 	addarchfile("irqalloc", 0444, irqallocread, nil);
+	addarchfile("irqstat", 0444, irqstatread, nil);
 	trapinited = 1;
 }
 
@@ -282,7 +313,7 @@ static char* excname[32] = {
 };
 
 /*
- *  keep histogram of interrupt service times
+ *  keep histogram of interrupt service times and count
  */
 void
 intrtime(Mach*, int vno)
@@ -302,6 +333,7 @@ intrtime(Mach*, int vno)
 	if(diff >= Ntimevec)
 		diff = Ntimevec-1;
 	intrtimes[vno][diff]++;
+	intrcount[vno]++;
 }
 
 /* go to user space */