diff --git a/test/jdk/java/net/httpclient/AbstractThrowingPublishers.java b/test/jdk/java/net/httpclient/AbstractThrowingPublishers.java
index f2a47734e40..4079bd81e3e 100644
--- a/test/jdk/java/net/httpclient/AbstractThrowingPublishers.java
+++ b/test/jdk/java/net/httpclient/AbstractThrowingPublishers.java
@@ -388,6 +388,24 @@ protected void testSanityImpl(String uri, boolean sameClient)
 
             String body = response.join().body();
             assertEquals(body, Stream.of(BODY.split("\\|")).collect(Collectors.joining()));
+            if (!sameClient) {
+                // Wait for the client to be garbage collected.
+                // we use the ReferenceTracker API rather than HttpClient::close here,
+                // because these tests inject faults by throwing inside callbacks, which
+                // is more likely to get HttpClient::close wedged until jtreg times out.
+                // By using the ReferenceTracker, we will get some diagnosis about what
+                // is keeping the client alive if it doesn't get GC'ed within the
+                // expected time frame.
+                var tracker = TRACKER.getTracker(client);
+                client = null;
+                System.gc();
+                System.out.println(now() + "waiting for client to shutdown: " + tracker.getName());
+                System.err.println(now() + "waiting for client to shutdown: " + tracker.getName());
+                var error = TRACKER.check(tracker, 10000);
+                if (error != null) throw error;
+                System.out.println(now() + "client shutdown normally: " + tracker.getName());
+                System.err.println(now() + "client shutdown normally: " + tracker.getName());
+            }
         }
     }
 
@@ -470,6 +488,24 @@ private void testThrowing(String uri, boolean sameClient,
             if (response != null) {
                 finisher.finish(where, response, thrower);
             }
+            if (!sameClient) {
+                // Wait for the client to be garbage collected.
+                // we use the ReferenceTracker API rather than HttpClient::close here,
+                // because these tests inject faults by throwing inside callbacks, which
+                // is more likely to get HttpClient::close wedged until jtreg times out.
+                // By using the ReferenceTracker, we will get some diagnosis about what
+                // is keeping the client alive if it doesn't get GC'ed within the
+                // expected time frame.
+                var tracker = TRACKER.getTracker(client);
+                client = null;
+                System.gc();
+                System.out.println(now() + "waiting for client to shutdown: " + tracker.getName());
+                System.err.println(now() + "waiting for client to shutdown: " + tracker.getName());
+                var error = TRACKER.check(tracker, 10000);
+                if (error != null) throw error;
+                System.out.println(now() + "client shutdown normally: " + tracker.getName());
+                System.err.println(now() + "client shutdown normally: " + tracker.getName());
+            }
         }
     }
 
diff --git a/test/jdk/java/net/httpclient/AbstractThrowingPushPromises.java b/test/jdk/java/net/httpclient/AbstractThrowingPushPromises.java
index a9d1906430d..b5230d48d10 100644
--- a/test/jdk/java/net/httpclient/AbstractThrowingPushPromises.java
+++ b/test/jdk/java/net/httpclient/AbstractThrowingPushPromises.java
@@ -340,6 +340,24 @@ public void applyPushPromise(HttpRequest initiatingRequest,
                 assertEquals(promisedBody, promised.uri().toASCIIString());
             }
             assertEquals(3, pushPromises.size());
+            if (!sameClient) {
+                // Wait for the client to be garbage collected.
+                // we use the ReferenceTracker API rather than HttpClient::close here,
+                // because these tests inject faults by throwing inside callbacks, which
+                // is more likely to get HttpClient::close wedged until jtreg times out.
+                // By using the ReferenceTracker, we will get some diagnosis about what
+                // is keeping the client alive if it doesn't get GC'ed within the
+                // expected time frame.
+                var tracker = TRACKER.getTracker(client);
+                client = null;
+                System.gc();
+                System.out.println(now() + "waiting for client to shutdown: " + tracker.getName());
+                System.err.println(now() + "waiting for client to shutdown: " + tracker.getName());
+                var error = TRACKER.check(tracker, 10000);
+                if (error != null) throw error;
+                System.out.println(now() + "client shutdown normally: " + tracker.getName());
+                System.err.println(now() + "client shutdown normally: " + tracker.getName());
+            }
         }
     }
 
@@ -425,6 +443,24 @@ private <T,U> void testThrowing(String uri, boolean sameClient,
             if (response != null) {
                 finisher.finish(where, req.uri(), response, thrower, promiseMap);
             }
+            if (!sameClient) {
+                // Wait for the client to be garbage collected.
+                // we use the ReferenceTracker API rather than HttpClient::close here,
+                // because these tests inject faults by throwing inside callbacks, which
+                // is more likely to get HttpClient::close wedged until jtreg times out.
+                // By using the ReferenceTracker, we will get some diagnosis about what
+                // is keeping the client alive if it doesn't get GC'ed within the
+                // expected time frame.
+                var tracker = TRACKER.getTracker(client);
+                client = null;
+                System.gc();
+                System.out.println(now() + "waiting for client to shutdown: " + tracker.getName());
+                System.err.println(now() + "waiting for client to shutdown: " + tracker.getName());
+                var error = TRACKER.check(tracker, 10000);
+                if (error != null) throw error;
+                System.out.println(now() + "client shutdown normally: " + tracker.getName());
+                System.err.println(now() + "client shutdown normally: " + tracker.getName());
+            }
         }
     }
 
diff --git a/test/jdk/java/net/httpclient/AbstractThrowingSubscribers.java b/test/jdk/java/net/httpclient/AbstractThrowingSubscribers.java
index 893950608b1..d4100b7eb04 100644
--- a/test/jdk/java/net/httpclient/AbstractThrowingSubscribers.java
+++ b/test/jdk/java/net/httpclient/AbstractThrowingSubscribers.java
@@ -314,6 +314,24 @@ protected void testSanityImpl(String uri, boolean sameClient)
             HttpResponse<String> response = client.send(req, handler);
             String body = response.body();
             assertEquals(URI.create(body).getPath(), URI.create(uri2).getPath());
+            if (!sameClient) {
+                // Wait for the client to be garbage collected.
+                // we use the ReferenceTracker API rather than HttpClient::close here,
+                // because these tests inject faults by throwing inside callbacks, which
+                // is more likely to get HttpClient::close wedged until jtreg times out.
+                // By using the ReferenceTracker, we will get some diagnosis about what
+                // is keeping the client alive if it doesn't get GC'ed within the
+                // expected time frame.
+                var tracker = TRACKER.getTracker(client);
+                client = null;
+                System.gc();
+                System.out.println(now() + "waiting for client to shutdown: " + tracker.getName());
+                System.err.println(now() + "waiting for client to shutdown: " + tracker.getName());
+                var error = TRACKER.check(tracker, 10000);
+                if (error != null) throw error;
+                System.out.println(now() + "client shutdown normally: " + tracker.getName());
+                System.err.println(now() + "client shutdown normally: " + tracker.getName());
+            }
         }
     }
 
@@ -461,6 +479,24 @@ private <T,U> void testThrowing(String uri, boolean sameClient,
             if (response != null) {
                 finisher.finish(where, response, thrower);
             }
+            if (!sameClient) {
+                // Wait for the client to be garbage collected.
+                // we use the ReferenceTracker API rather than HttpClient::close here,
+                // because these tests inject faults by throwing inside callbacks, which
+                // is more likely to get HttpClient::close wedged until jtreg times out.
+                // By using the ReferenceTracker, we will get some diagnosis about what
+                // is keeping the client alive if it doesn't get GC'ed within the
+                // expected time frame.
+                var tracker = TRACKER.getTracker(client);
+                client = null;
+                System.gc();
+                System.out.println(now() + "waiting for client to shutdown: " + tracker.getName());
+                System.err.println(now() + "waiting for client to shutdown: " + tracker.getName());
+                var error = TRACKER.check(tracker, 10000);
+                if (error != null) throw error;
+                System.out.println(now() + "client shutdown normally: " + tracker.getName());
+                System.err.println(now() + "client shutdown normally: " + tracker.getName());
+            }
         }
     }