diff --git a/src/emu/CMakeLists.txt b/src/emu/CMakeLists.txt
index dce8776..39e5694 100644
--- a/src/emu/CMakeLists.txt
+++ b/src/emu/CMakeLists.txt
@@ -35,6 +35,7 @@ add_library(emu STATIC
   thread.c
   extend.c
   ovni/probe.c
+  ovni/create.c
   ovni/event.c
   nanos6/probe.c
   nanos6/connect.c
diff --git a/src/emu/extend.h b/src/emu/extend.h
index b948d82..eb6333f 100644
--- a/src/emu/extend.h
+++ b/src/emu/extend.h
@@ -13,4 +13,6 @@ struct extend {
 void extend_set(struct extend *ext, int id, void *ctx);
 void *extend_get(struct extend *ext, int id);
 
+#define EXT(st, m) extend_get(&(st)->ext, (m))
+
 #endif /* EXTEND_H */
diff --git a/src/emu/model.c b/src/emu/model.c
index abe86db..d6af3dd 100644
--- a/src/emu/model.c
+++ b/src/emu/model.c
@@ -31,10 +31,14 @@ model_probe(struct model *model, struct emu *emu)
 		if (spec->probe == NULL)
 			continue;
 
-		if (spec->probe(emu) != 0) {
+		int ret = spec->probe(emu);
+		if (ret < 0) {
 			err("probe failed for model '%c'", (char) i);
 			return -1;
 		}
+
+		if (ret == 0)
+			model->enabled[i] = 1;
 	}
 	return 0;
 }
@@ -43,7 +47,7 @@ int
 model_create(struct model *model, struct emu *emu)
 {
 	for (int i = 0; i < MAX_MODELS; i++) {
-		if (!model->registered[i])
+		if (!model->enabled[i])
 			continue;
 
 		struct model_spec *spec = model->spec[i];
@@ -62,7 +66,7 @@ int
 model_connect(struct model *model, struct emu *emu)
 {
 	for (int i = 0; i < MAX_MODELS; i++) {
-		if (!model->registered[i])
+		if (!model->enabled[i])
 			continue;
 
 		struct model_spec *spec = model->spec[i];
@@ -81,7 +85,12 @@ int
 model_event(struct model *model, struct emu *emu, int index)
 {
 	if (!model->registered[index]) {
-		err("no model registered for '%c'", (char) index);
+		err("model not registered for '%c'", (char) index);
+		return -1;
+	}
+
+	if (!model->enabled[index]) {
+		err("model not enabled for '%c'", (char) index);
 		return -1;
 	}
 
diff --git a/src/emu/model.h b/src/emu/model.h
index c5d109e..c5333d2 100644
--- a/src/emu/model.h
+++ b/src/emu/model.h
@@ -21,6 +21,7 @@ struct model_spec {
 struct model {
 	struct model_spec *spec[MAX_MODELS];
 	int registered[MAX_MODELS];
+	int enabled[MAX_MODELS];
 };
 
 void model_init(struct model *model);
diff --git a/src/emu/nanos6/probe.c b/src/emu/nanos6/probe.c
index c0b5f82..72befa6 100644
--- a/src/emu/nanos6/probe.c
+++ b/src/emu/nanos6/probe.c
@@ -13,7 +13,7 @@ int
 nanos6_probe(struct emu *emu)
 {
 	if (emu->system.nthreads == 0)
-		return -1;
+		return 1;
 
 	return 0;
 }
diff --git a/src/emu/ovni/connect.c b/src/emu/ovni/connect.c
new file mode 100644
index 0000000..166ae13
--- /dev/null
+++ b/src/emu/ovni/connect.c
@@ -0,0 +1,181 @@
+#include "ovni_priv.h"
+
+static const int th_type[] = {
+	[CH_FLUSH] = 7,
+};
+
+static const int *cpu_type = th_type;
+
+
+static int
+connect_thread_mux(struct emu *emu, struct thread *thread)
+{
+	struct ovni_thread *th = extend_get(&thread->ext, 'O');
+	for (int i = 0; i < CH_MAX; i++) {
+		struct chan *inp = &th->ch[i];
+		struct chan *sel = &thread->chan[TH_CHAN_STATE];
+		struct mux *mux_run = &th->mux_run[i];
+		mux_select_func_t selrun = thread_select_running;
+		if (mux_init(mux_run, &emu->bay, sel, &th->ch_run[i], selrun) != 0) {
+			err("mux_init failed");
+			return -1;
+		}
+
+		if (mux_add_input(mux_run, value_int64(0), inp) != 0) {
+			err("mux_add_input failed");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int
+connect_thread_prv(struct emu *emu, struct thread *thread, struct prv *prv)
+{
+	struct ovni_thread *th = extend_get(&thread->ext, 'O');
+	for (int i = 0; i < CH_MAX; i++) {
+		struct chan *out = th->ch_out[i];
+		long type = th_type[i];
+		long row = thread->gindex;
+		if (prv_register(prv, row, type, &emu->bay, out, PRV_DUP)) {
+			err("prv_register failed");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int
+add_inputs_cpu_mux(struct emu *emu, struct mux *mux, int i)
+{
+	for (struct thread *t = emu->system.threads; t; t = t->gnext) {
+		struct ovni_thread *th = extend_get(&t->ext, 'O');
+		struct chan *inp = &th->ch_run[i];
+		if (mux_add_input(mux, value_int64(t->gindex), inp) != 0) {
+			err("mux_add_input failed");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int
+connect_cpu_mux(struct emu *emu, struct cpu *scpu)
+{
+	struct ovni_cpu *cpu = extend_get(&scpu->ext, 'O');
+	for (int i = 0; i < CH_MAX; i++) {
+		struct mux *mux = &cpu->mux[i];
+		struct chan *out = &cpu->ch[i];
+		struct chan *sel = &scpu->chan[CPU_CHAN_THRUN];
+
+		if (mux_init(mux, &emu->bay, sel, out, NULL) != 0) {
+			err("mux_init failed");
+			return -1;
+		}
+
+		if (add_inputs_cpu_mux(emu, mux, i) != 0) {
+			err("add_inputs_cpu_mux failed");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int
+connect_threads(struct emu *emu)
+{
+	struct system *sys = &emu->system;
+
+	/* threads */
+	for (struct thread *t = sys->threads; t; t = t->gnext) {
+		if (connect_thread_mux(emu, t) != 0) {
+			err("connect_thread_mux failed");
+			return -1;
+		}
+	}
+
+	/* Get thread PRV */
+	struct pvt *pvt = recorder_find_pvt(&emu->recorder, "thread");
+	if (pvt == NULL) {
+		err("cannot find thread pvt");
+		return -1;
+	}
+	struct prv *prv = pvt_get_prv(pvt);
+
+	for (struct thread *t = sys->threads; t; t = t->gnext) {
+		if (connect_thread_prv(emu, t, prv) != 0) {
+			err("connect_thread_prv failed");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int
+connect_cpu_prv(struct emu *emu, struct cpu *scpu, struct prv *prv)
+{
+	struct ovni_cpu *cpu = extend_get(&scpu->ext, 'O');
+	for (int i = 0; i < CH_MAX; i++) {
+		struct chan *out = &cpu->ch[i];
+		long type = cpu_type[i];
+		long row = scpu->gindex;
+		if (prv_register(prv, row, type, &emu->bay, out, PRV_DUP)) {
+			err("prv_register failed");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int
+connect_cpus(struct emu *emu)
+{
+	struct system *sys = &emu->system;
+
+	/* cpus */
+	for (struct cpu *c = sys->cpus; c; c = c->next) {
+		if (connect_cpu_mux(emu, c) != 0) {
+			err("connect_cpu_mux failed");
+			return -1;
+		}
+	}
+
+	/* Get cpu PRV */
+	struct pvt *pvt = recorder_find_pvt(&emu->recorder, "cpu");
+	if (pvt == NULL) {
+		err("cannot find cpu pvt");
+		return -1;
+	}
+	struct prv *prv = pvt_get_prv(pvt);
+
+	for (struct cpu *c = sys->cpus; c; c = c->next) {
+		if (connect_cpu_prv(emu, c, prv) != 0) {
+			err("connect_cpu_prv failed");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+int
+ovni_connect(struct emu *emu)
+{
+	if (connect_threads(emu) != 0) {
+		err("connect_threads failed");
+		return -1;
+	}
+
+	if (connect_cpus(emu) != 0) {
+		err("connect_cpus failed");
+		return -1;
+	}
+
+	return 0;
+}
diff --git a/src/emu/ovni/create.c b/src/emu/ovni/create.c
new file mode 100644
index 0000000..bd0e6f8
--- /dev/null
+++ b/src/emu/ovni/create.c
@@ -0,0 +1,90 @@
+#include "ovni_priv.h"
+
+static const char chan_fmt_cpu[] = "ovni.cpu%ld.%s";
+static const char chan_fmt_th_raw[] = "ovni.thread%ld.%s.raw";
+static const char chan_fmt_th_run[] = "ovni.thread%ld.%s.run";
+
+static const char *chan_name[] = {
+	[CH_FLUSH] = "flush",
+};
+
+static int
+init_chans(struct bay *bay, struct chan *chans, const char *fmt, int64_t gindex)
+{
+	for (int i = 0; i < CH_MAX; i++) {
+		struct chan *c = &chans[i];
+		chan_init(c, CHAN_SINGLE, fmt, gindex, chan_name[i]);
+
+		if (bay_register(bay, c) != 0) {
+			err("bay_register failed");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int
+init_cpu(struct bay *bay, struct cpu *syscpu)
+{
+	struct ovni_cpu *cpu = calloc(1, sizeof(struct ovni_cpu));
+	if (cpu == NULL) {
+		err("calloc failed:");
+		return -1;
+	}
+
+	if (init_chans(bay, cpu->ch, chan_fmt_cpu, syscpu->gindex) != 0) {
+		err("init_chans failed");
+		return -1;
+	}
+
+	extend_set(&syscpu->ext, 'O', cpu);
+	return 0;
+}
+
+static int
+init_thread(struct bay *bay, struct thread *systh)
+{
+	struct ovni_thread *th = calloc(1, sizeof(struct ovni_thread));
+	if (th == NULL) {
+		err("calloc failed:");
+		return -1;
+	}
+
+	if (init_chans(bay, th->ch, chan_fmt_th_raw, systh->gindex) != 0) {
+		err("init_chans failed");
+		return -1;
+	}
+
+	if (init_chans(bay, th->ch_run, chan_fmt_th_run, systh->gindex) != 0) {
+		err("init_chans failed");
+		return -1;
+	}
+
+	extend_set(&systh->ext, 'O', th);
+
+	return 0;
+}
+
+int
+ovni_create(struct emu *emu)
+{
+	struct system *sys = &emu->system;
+	struct bay *bay = &emu->bay;
+
+	for (struct cpu *c = sys->cpus; c; c = c->next) {
+		if (init_cpu(bay, c) != 0) {
+			err("init_cpu failed");
+			return -1;
+		}
+	}
+
+	for (struct thread *t = sys->threads; t; t = t->gnext) {
+		if (init_thread(bay, t) != 0) {
+			err("init_thread failed");
+			return -1;
+		}
+	}
+
+	return 0;
+}
diff --git a/src/emu/ovni/event.c b/src/emu/ovni/event.c
index 04467b6..ca25fd5 100644
--- a/src/emu/ovni/event.c
+++ b/src/emu/ovni/event.c
@@ -301,80 +301,83 @@ pre_affinity(struct emu *emu)
 		default:
 			err("unknown affinity event value %c\n",
 					emu->ev->v);
-//			return -1
+			return -1;
 	}
 
 	return 0;
 }
 
-//static int
-//compare_int64(const void *a, const void *b)
-//{
-//	int64_t aa = *(const int64_t *) a;
-//	int64_t bb = *(const int64_t *) b;
-//
-//	if (aa < bb)
-//		return -1;
-//	else if (aa > bb)
-//		return +1;
-//	else
-//		return 0;
-//}
+static int
+compare_int64(const void *a, const void *b)
+{
+	int64_t aa = *(const int64_t *) a;
+	int64_t bb = *(const int64_t *) b;
 
-//static int
-//pre_burst(struct emu *emu)
-//{
-//	struct thread *th = emu->thread;
-//
-//	if (th->nbursts >= MAX_BURSTS) {
-//		err("too many bursts");
-//		return -1;
-//	}
-//
-//	th->burst_time[th->nbursts++] = emu->delta_time;
-//	if (th->nbursts == MAX_BURSTS) {
-//		int n = MAX_BURSTS - 1;
-//		int64_t deltas[MAX_BURSTS - 1];
-//		for (int i = 0; i < n; i++) {
-//			deltas[i] = th->burst_time[i + 1] - th->burst_time[i];
-//		}
-//
-//		qsort(deltas, n, sizeof(int64_t), compare_int64);
-//
-//		double avg = 0.0;
-//		double maxdelta = 0;
-//		for (int i = 0; i < n; i++) {
-//			if (deltas[i] > maxdelta)
-//				maxdelta = deltas[i];
-//			avg += deltas[i];
-//		}
-//
-//		avg /= (double) n;
-//		double median = deltas[n / 2];
-//
-//		err("%s burst stats: median %.0f ns, avg %.1f ns, max %.0f ns\n",
-//				emu->cur_loom->dname, median, avg, maxdelta);
-//
-//		th->nbursts = 0;
-//	}
-//}
+	if (aa < bb)
+		return -1;
+	else if (aa > bb)
+		return +1;
+	else
+		return 0;
+}
+
+static int
+pre_burst(struct emu *emu)
+{
+	struct ovni_thread *th = EXT(emu->thread, 'O');
+
+	if (th->nbursts >= MAX_BURSTS) {
+		err("too many bursts");
+		return -1;
+	}
+
+	th->burst_time[th->nbursts++] = emu->ev->dclock;
+
+	if (th->nbursts != MAX_BURSTS)
+		return 0;
+
+	int n = MAX_BURSTS - 1;
+	int64_t deltas[MAX_BURSTS - 1];
+	for (int i = 0; i < n; i++)
+		deltas[i] = th->burst_time[i + 1] - th->burst_time[i];
+
+	qsort(deltas, n, sizeof(int64_t), compare_int64);
+
+	double avg = 0.0;
+	double maxdelta = 0;
+	for (int i = 0; i < n; i++) {
+		if (deltas[i] > maxdelta)
+			maxdelta = deltas[i];
+		avg += deltas[i];
+	}
+
+	avg /= (double) n;
+	double median = deltas[n / 2];
+
+	err("%s burst stats: median %.0f ns, avg %.1f ns, max %.0f ns\n",
+			emu->loom->id, median, avg, maxdelta);
+
+	th->nbursts = 0;
+
+	return 0;
+}
 
 static int
 pre_flush(struct emu *emu)
 {
-	struct thread *th = emu->thread;
-	struct chan *flush = &th->chan[TH_CHAN_FLUSH];
+	struct ovni_thread *th = extend_get(&emu->thread->ext, 'O');
+	struct chan *flush = &th->ch[CH_FLUSH];
 
 	switch (emu->ev->v) {
 		case '[':
-			if (chan_push(flush, value_int64(1)) != 0) {
-				err("chan_push failed");
+			if (chan_set(flush, value_int64(1)) != 0) {
+				err("chan_set failed");
 				return -1;
 			}
 			break;
 		case ']':
-			if (chan_pop(flush, value_int64(1)) != 0) {
-				err("chan_pop failed");
+			if (chan_set(flush, value_null()) != 0) {
+				err("chan_set failed");
 				return -1;
 			}
 			break;
@@ -398,15 +401,15 @@ process_ev(struct emu *emu)
 			return pre_thread(emu);
 		case 'A':
 			return pre_affinity(emu);
-//		case 'B':
-//			pre_burst(emu);
-//			break;
+		case 'B':
+			pre_burst(emu);
+			break;
 		case 'F':
 			return pre_flush(emu);
 		default:
 			err("unknown ovni event category %c\n",
 					emu->ev->c);
-//			return -1;
+			return -1;
 	}
 
 	return 0;
diff --git a/src/emu/ovni/ovni_priv.h b/src/emu/ovni/ovni_priv.h
index 074753a..2d473f9 100644
--- a/src/emu/ovni/ovni_priv.h
+++ b/src/emu/ovni/ovni_priv.h
@@ -6,23 +6,37 @@
 
 /* The user-space thread "ovni" execution model tracks the state of processes and
  * threads running in the CPUs by instrumenting the threads before and after
- * they are going to sleep. It jovni provides an approximate view of the real
+ * they are going to sleep. It just provides an approximate view of the real
  * execution by the kernel. */
 
 #include "emu.h"
 #include "chan.h"
+#include <stdint.h>
 
 enum ovni_chan_type {
-	UST_CHAN_FLUSH = 0,
-	UST_CHAN_BURST,
-	UST_CHAN_MAX,
+	CH_FLUSH = 0,
+	CH_MAX,
 };
 
+#define MAX_BURSTS 100
+
 struct ovni_thread {
-	struct chan chan[UST_CHAN_MAX];
+	struct chan ch[CH_MAX];
+	struct chan ch_run[CH_MAX];
+	struct chan mux_run[CH_MAX];
+
+	/* Burst times */
+	int nbursts;
+	int64_t burst_time[MAX_BURSTS];
+};
+
+struct ovni_cpu {
+	struct chan ch[CH_MAX];
+	struct mux mux[CH_MAX];
 };
 
 int ovni_probe(struct emu *emu);
+int ovni_create(struct emu *emu);
 int ovni_event(struct emu *emu);
 
 #endif /* OVNI_PRIV_H */
diff --git a/src/emu/ovni/probe.c b/src/emu/ovni/probe.c
index e7d6580..566901b 100644
--- a/src/emu/ovni/probe.c
+++ b/src/emu/ovni/probe.c
@@ -6,7 +6,7 @@
 struct model_spec model_ovni = {
 	.name = "ovni",
 	.model = 'O',
-	.create  = NULL,
+	.create  = ovni_create,
 	.connect = NULL,
 	.event   = ovni_event,
 	.probe   = ovni_probe,
@@ -16,7 +16,7 @@ int
 ovni_probe(struct emu *emu)
 {
 	if (emu->system.nthreads == 0)
-		return -1;
+		return 1;
 
 	return 0;
 }
diff --git a/src/emu/thread.c b/src/emu/thread.c
index a8bd0ab..80686d6 100644
--- a/src/emu/thread.c
+++ b/src/emu/thread.c
@@ -11,18 +11,12 @@ static const char *chan_name[] = {
 	[TH_CHAN_CPU] = "cpu_gindex",
 	[TH_CHAN_TID] = "tid_active",
 	[TH_CHAN_STATE] = "state",
-	[TH_CHAN_FLUSH] = "flush",
-};
-
-static const int chan_stack[] = {
-	[TH_CHAN_FLUSH] = 1,
 };
 
 static const int chan_type[] = {
 	[TH_CHAN_TID] = 2,
 	[TH_CHAN_STATE] = 4,
 	[TH_CHAN_CPU] = 6,
-	[TH_CHAN_FLUSH] = 7,
 };
 
 static int
@@ -103,12 +97,7 @@ thread_init_end(struct thread *th)
 	}
 
 	for (int i = 0; i < TH_CHAN_MAX; i++) {
-		enum chan_type type = CHAN_SINGLE;
-
-		if (chan_stack[i])
-			type = CHAN_STACK;
-
-		chan_init(&th->chan[i], type,
+		chan_init(&th->chan[i], CHAN_SINGLE,
 				chan_fmt, th->gindex, chan_name[i]);
 	}
 
diff --git a/src/emu/thread.h b/src/emu/thread.h
index 4f604b1..9cc7711 100644
--- a/src/emu/thread.h
+++ b/src/emu/thread.h
@@ -31,7 +31,6 @@ enum thread_chan {
 	TH_CHAN_CPU = 0,
 	TH_CHAN_TID,
 	TH_CHAN_STATE,
-	TH_CHAN_FLUSH,
 	TH_CHAN_MAX,
 };