diff --git a/test/emu/ovni/CMakeLists.txt b/test/emu/ovni/CMakeLists.txt
index 51945ba..d8665da 100644
--- a/test/emu/ovni/CMakeLists.txt
+++ b/test/emu/ovni/CMakeLists.txt
@@ -7,5 +7,7 @@ if(CMAKE_BUILD_TYPE STREQUAL "Release")
 endif()
 
 ovni_test(flush.c)
+ovni_test(sort.c SORT)
+ovni_test(empty-sort.c SORT)
 ovni_test(mp-simple.c MP)
 ovni_test(mp-rank.c MP)
diff --git a/test/emu/ovni/empty-sort.c b/test/emu/ovni/empty-sort.c
new file mode 100644
index 0000000..29c67c0
--- /dev/null
+++ b/test/emu/ovni/empty-sort.c
@@ -0,0 +1,67 @@
+/* Copyright (c) 2021-2022 Barcelona Supercomputing Center (BSC)
+ * SPDX-License-Identifier: GPL-3.0-or-later */
+
+#define _POSIX_C_SOURCE 200112L
+#define _GNU_SOURCE
+
+#include <limits.h>
+#include <linux/limits.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "compat.h"
+#include "ovni.h"
+
+static inline void
+init(void)
+{
+	char hostname[HOST_NAME_MAX];
+
+	if (gethostname(hostname, HOST_NAME_MAX) != 0) {
+		perror("gethostname failed");
+		exit(EXIT_FAILURE);
+	}
+
+	ovni_proc_init(0, hostname, getpid());
+	ovni_thread_init(gettid());
+	ovni_add_cpu(0, 0);
+}
+
+static void
+emit(char *mcv, int64_t clock)
+{
+	struct ovni_ev ev = {0};
+	ovni_ev_set_mcv(&ev, mcv);
+	ovni_ev_set_clock(&ev, clock);
+	ovni_ev_emit(&ev);
+}
+
+int
+main(void)
+{
+	init();
+
+	/* Leave some room to prevent clashes */
+	usleep(100); /* 100000 us */
+
+	int64_t t0 = ovni_clock_now();
+
+	emit("OU[", t0);
+
+	int64_t t = t0 - 10000;
+	for (int i = 0; i < 100; i++) {
+		emit("OB.", t);
+		t += 33;
+	}
+
+	emit("OU]", ovni_clock_now());
+
+	ovni_flush();
+	ovni_proc_fini();
+
+	return 0;
+}
diff --git a/test/emu/ovni/sort.c b/test/emu/ovni/sort.c
new file mode 100644
index 0000000..bc1f463
--- /dev/null
+++ b/test/emu/ovni/sort.c
@@ -0,0 +1,70 @@
+/* Copyright (c) 2021-2022 Barcelona Supercomputing Center (BSC)
+ * SPDX-License-Identifier: GPL-3.0-or-later */
+
+#define _POSIX_C_SOURCE 200112L
+#define _GNU_SOURCE
+
+#include <limits.h>
+#include <linux/limits.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "compat.h"
+#include "ovni.h"
+#include "../instr.h"
+
+static void
+emit_jumbo(uint8_t *buf, size_t size, int64_t clock)
+{
+	struct ovni_ev ev = {0};
+	ovni_ev_set_mcv(&ev, "O$$");
+	ovni_ev_set_clock(&ev, clock);
+	ovni_ev_jumbo_emit(&ev, buf, size);
+}
+
+static void
+emit(char *mcv, int64_t clock)
+{
+	struct ovni_ev ev = {0};
+	ovni_ev_set_mcv(&ev, mcv);
+	ovni_ev_set_clock(&ev, clock);
+	ovni_ev_emit(&ev);
+}
+
+#define BUFSIZE 128
+
+int
+main(void)
+{
+	uint8_t buf[BUFSIZE];
+	instr_start(0, 1);
+
+	/* Leave some room to prevent clashes */
+	usleep(100); /* 100000 us */
+
+	int64_t t0 = ovni_clock_now();
+
+	emit("OU[", t0);
+
+	int64_t t = t0 - 10000;
+	for (int i = 0; i < 100; i++) {
+		emit("OB.", t);
+		t += 33;
+	}
+
+	/* Also test jumbo events */
+	for (int i = 0; i < BUFSIZE; i++)
+		buf[i] = i & 0xff;
+
+	emit_jumbo(buf, BUFSIZE, t);
+
+	emit("OU]", ovni_clock_now());
+
+	instr_end();
+
+	return 0;
+}