diff --git a/emu.c b/emu.c
index 2345ab9..33bae68 100644
--- a/emu.c
+++ b/emu.c
@@ -707,6 +707,14 @@ open_pcfs(struct ovni_emu *emu, char *tracedir)
 	}
 }
 
+/* Fix the trace duration at the end */
+static void
+fix_prv_headers(struct ovni_emu *emu)
+{
+	prv_fix_header(emu->prv_thread, emu->delta_time, emu->total_nthreads);
+	prv_fix_header(emu->prv_cpu, emu->delta_time, emu->total_ncpus);
+}
+
 static void
 close_prvs(struct ovni_emu *emu)
 {
@@ -1084,6 +1092,7 @@ emu_post(struct ovni_emu *emu)
 static void
 emu_destroy(struct ovni_emu *emu)
 {
+	fix_prv_headers(emu);
 	close_prvs(emu);
 	close_pcfs(emu);
 	destroy_metadata(emu);
diff --git a/prv.c b/prv.c
index bdf6975..d7104f1 100644
--- a/prv.c
+++ b/prv.c
@@ -81,5 +81,13 @@ prv_ev_autocpu(struct ovni_emu *emu, int type, int val)
 void
 prv_header(FILE *f, int nrows)
 {
-	fprintf(f, "#Paraver (19/01/38 at 03:14):00000000000000000000_ns:0:1:1(%d:1)\n", nrows);
+	fprintf(f, "#Paraver (19/01/38 at 03:14):%020ld_ns:0:1:1(%d:1)\n", 0LU, nrows);
+}
+
+void
+prv_fix_header(FILE *f, uint64_t duration, int nrows)
+{
+	/* Go to the first byte */
+	fseek(f, 0, SEEK_SET);
+	fprintf(f, "#Paraver (19/01/38 at 03:14):%020ld_ns:0:1:1(%d:1)\n", duration, nrows);
 }
diff --git a/prv.h b/prv.h
index ec3ddb9..de244b5 100644
--- a/prv.h
+++ b/prv.h
@@ -43,4 +43,7 @@ prv_ev_autocpu_raw(struct ovni_emu *emu, int64_t time, int type, int val);
 void
 prv_header(FILE *f, int nrows);
 
+void
+prv_fix_header(FILE *f, uint64_t duration, int nrows);
+
 #endif /* OVNI_PRV_H */