[PATCH 2/2] test: Adjust sync timing

From: Eugene Loh <[email protected]>

The nusdtprobes test was failing rather consistently on systems with
very large CPU counts.

The main problem was that dtrace programs with aggregations take a long
time to start up on such systems.  In particular, gmap_create_aggs()
tries to create an aggs_$cpu BPF map for each CPU, spending (in
measurements on one system) about 0.004 sec for each dt_bpf_map_create()
and 0.011 sec for each dt_bpf_map_update().  When there are hundreds of
CPUs, the time to start the job up increases by, for example, 5-6
seconds.  The test waits for dtrace to start up by checking "-e" on the
output file, but the aggs_$cpu delay occurs after the file is created.

Add a BEGIN clause to write to the output file.  Replace the "-e" test
with "-s".

The test has a sleep before starting a team of processes.  There is
perhaps no reason for this wait.  Nonetheless, we leave that sleep,
simply reducing the time to 1 second.

There is also a delay between launching processes and tracing them:

  x dtprobed sees newly launched processes rather quickly
  x dtrace tries discovery 1x/second
  x discovery is rather fast
  x starting a newly discovered probe is ~ 0.011sec (on one system)

For 40 probes, that last step is about 0.5 sec, but the total "sleep 3"
in the test before killing the new processes is apparently sufficient.

Make the corresponding "-e" to "-s" change in similar tests, even if
they have not shown the failure pattern.

Signed-off-by: Eugene Loh <[email protected]>
---
 test/unittest/usdt/tst.defer-Z-basic.sh | 10 +++++++---
 test/unittest/usdt/tst.defer-Z.sh       | 10 +++++++---
 test/unittest/usdt/tst.defer.sh         | 10 +++++++---
 test/unittest/usdt/tst.nusdtprobes.sh   | 10 +++++++---
 4 files changed, 28 insertions(+), 12 deletions(-)

diff --git a/test/unittest/usdt/tst.defer-Z-basic.sh b/test/unittest/usdt/tst.defer-Z-basic.sh
index 61adb4601..fad91e5fe 100755
--- a/test/unittest/usdt/tst.defer-Z-basic.sh
+++ b/test/unittest/usdt/tst.defer-Z-basic.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 #
 # Oracle Linux DTrace.
-# Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2025, 2026, Oracle and/or its affiliates. All rights reserved.
 # Licensed under the Universal Permissive License v 1.0 as shown at
 # http://oss.oracle.com/licenses/upl.
 #
@@ -22,6 +22,10 @@ cp $trigger main
 
 # Start dtrace.
 $dtrace $dt_flags -Zq -o dtrace.out -n '
+BEGIN
+{
+	printf("BEGIN\n");
+}
 testprov*:::foo,
 testprov*:::bar
 {
@@ -33,7 +37,7 @@ dtpid=$!
 iter=$((timeout / 2))
 while [ $iter -gt 0 ]; do
 	sleep 1
-	if [ -e dtrace.out ]; then
+	if [ -s dtrace.out ]; then
 		break
 	fi
 	iter=$((iter - 1))
@@ -79,7 +83,7 @@ if ! diff -q main.out.post main.out.expected; then
 fi
 
 # Regularize the DTrace output, and check it.
-awk 'NF > 0 { map[$2 " " $1]++; }
+awk 'NF > 1 { map[$2 " " $1]++; }
      END { for (i in map) printf "%s %d\n", i, map[i]; }' dtrace.out > dtrace.out.post
 
 echo "$tpid main:bar 10" > dtrace.out.expected
diff --git a/test/unittest/usdt/tst.defer-Z.sh b/test/unittest/usdt/tst.defer-Z.sh
index ff2c5cbf1..db49cd583 100755
--- a/test/unittest/usdt/tst.defer-Z.sh
+++ b/test/unittest/usdt/tst.defer-Z.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 #
 # Oracle Linux DTrace.
-# Copyright (c) 2024, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2024, 2026, Oracle and/or its affiliates. All rights reserved.
 # Licensed under the Universal Permissive License v 1.0 as shown at
 # http://oss.oracle.com/licenses/upl.
 #
@@ -29,6 +29,10 @@ cp $trigger main
 # Start dtrace.
 
 $dtrace $dt_flags -Zwq -o dtrace.out -n '
+BEGIN
+{
+	printf("BEGIN\n");
+}
 testprov*:::foo
 {
 	raise(SIGUSR1);
@@ -51,7 +55,7 @@ dtpid=$!
 iter=$((timeout / 2))
 while [ $iter -gt 0 ]; do
 	sleep 1
-	if [ -e dtrace.out ]; then
+	if [ -s dtrace.out ]; then
 		break
 	fi
 	iter=$((iter - 1))
@@ -128,7 +132,7 @@ done
 # Check the dtrace output.
 
 #     regularize the dtrace output
-awk 'NF != 0 { print $1, $2, $3 }' dtrace.out | sort > dtrace.out.post
+awk 'NF == 3 { print $1, $2, $3 }' dtrace.out | sort > dtrace.out.post
 
 #     determine what to expect
 
diff --git a/test/unittest/usdt/tst.defer.sh b/test/unittest/usdt/tst.defer.sh
index 073af12d5..a1c29571c 100755
--- a/test/unittest/usdt/tst.defer.sh
+++ b/test/unittest/usdt/tst.defer.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 #
 # Oracle Linux DTrace.
-# Copyright (c) 2024, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2024, 2026, Oracle and/or its affiliates. All rights reserved.
 # Licensed under the Universal Permissive License v 1.0 as shown at
 # http://oss.oracle.com/licenses/upl.
 #
@@ -39,6 +39,10 @@ lastdigit=$((${pids[0]} % 10))
 # Start dtrace.
 
 $dtrace $dt_flags -wq -o dtrace.out -n '
+BEGIN
+{
+	printf("BEGIN\n");
+}
 testprov*:::foo
 {
 	raise(SIGUSR1);
@@ -57,7 +61,7 @@ dtpid=$!
 iter=$((timeout / 2))
 while [ $iter -gt 0 ]; do
 	sleep 1
-	if [ -e dtrace.out ]; then
+	if [ -s dtrace.out ]; then
 		break
 	fi
 	iter=$((iter - 1))
@@ -135,7 +139,7 @@ done
 # Check the dtrace output.
 
 #     regularize the dtrace output
-awk 'NF != 0 { print $1, $2, $3 }' dtrace.out | sort > dtrace.out.post
+awk 'NF == 3 { print $1, $2, $3 }' dtrace.out | sort > dtrace.out.post
 
 #     determine what to expect
 
diff --git a/test/unittest/usdt/tst.nusdtprobes.sh b/test/unittest/usdt/tst.nusdtprobes.sh
index 93c56e382..5e3a49724 100755
--- a/test/unittest/usdt/tst.nusdtprobes.sh
+++ b/test/unittest/usdt/tst.nusdtprobes.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 #
 # Oracle Linux DTrace.
-# Copyright (c) 2024, 2025, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2024, 2026, Oracle and/or its affiliates. All rights reserved.
 # Licensed under the Universal Permissive License v 1.0 as shown at
 # http://oss.oracle.com/licenses/upl.
 #
@@ -100,6 +100,10 @@ for nusdt in "" "-xnusdtprobes=40" "-xnusdtprobes=39"; do
 
 	rm -f dtrace.out
 	$dtrace $dt_flags $nusdt -Zq -o dtrace.out -n '
+	BEGIN
+	{
+		printf("BEGIN\n");
+	}
 	testprov*:::
 	{
 		@[probeprov, probemod, probefunc, probename] = count();
@@ -111,7 +115,7 @@ for nusdt in "" "-xnusdtprobes=40" "-xnusdtprobes=39"; do
 	iter=$((timeout / 4))
 	while [ $iter -gt 0 ]; do
 		sleep 1
-		if [ -e dtrace.out ]; then
+		if [ -s dtrace.out ]; then
 			break
 		fi
 		iter=$((iter - 1))
@@ -127,7 +131,7 @@ for nusdt in "" "-xnusdtprobes=40" "-xnusdtprobes=39"; do
 	rm -f check.txt
 	for (( iteam = 0; iteam < $nteams; iteam++ )); do
 		# Start the team, writing out expected output.
-		sleep 2
+		sleep 1
 		for (( immbr = 0; immbr < $nmmbrs; immbr++ )); do
 			./main &
 			pids[$immbr]=$!
-- 
2.47.3