commit 63756be33f414d5cd7b744a2edee7875717d470c
author Austin Schuh <austin.schuh@bluerivertech.com> Mon Feb 05 19:51:20 2024 -0800
committer Austin Schuh <austin.linux@gmail.com> Sat May 11 14:14:43 2024 -0700
tree 53d70eb9d765d0f01815c96cfb6fb6118c81ffad
parent 36d7793ebe6c2301dff9e6c0ef78d9c776cf0931

Reduce flakeness of shm_event_loop_test

On some platforms, we were seeing one of the send too fast tests fail
occasionally.  Fix it by giving the scheduler a bit more of a grace
period by sending batches of messages and waking up less often, and
running it on the RT scheduler to reduce impact of other load.

Change-Id: I940dc58e81fed0e7ab8ef4da6b089226bfbc9945
Signed-off-by: James Kuszmaul <james.kuszmaul@bluerivertech.com>

aos/events/event_loop_param_test.cc

diff --git a/aos/events/event_loop_param_test.cc b/aos/events/event_loop_param_test.cc
index 58bfd9b..3fb9e9a 100644
--- a/aos/events/event_loop_param_test.cc
+++ b/aos/events/event_loop_param_test.cc
@@ -3553,6 +3553,7 @@
 // RawSender::Error::kMessagesSentTooFast.
 TEST_P(AbstractEventLoopTest, SendingMessagesTooFast) {
   auto event_loop = MakePrimary();
+  event_loop->SetRuntimeRealtimePriority(5);
 
   auto sender = event_loop->MakeSender<TestMessage>("/test");
 
@@ -3567,21 +3568,29 @@
   int msgs_sent = 1;
   const int queue_size = TestChannelQueueSize(event_loop.get());
 
+  const int messages_per_ms = 2;
+  const auto kRepeatOffset = std::chrono::milliseconds(10);
+  const auto base_offset =
+      configuration::ChannelStorageDuration(event_loop->configuration(),
+                                            sender.channel()) -
+      (std::chrono::milliseconds(1) * (queue_size / 2) / messages_per_ms);
+
   const auto timer = event_loop->AddTimer([&]() {
-    const bool done = (msgs_sent == queue_size + 1);
-    ASSERT_EQ(
-        SendTestMessage(sender),
-        done ? RawSender::Error::kMessagesSentTooFast : RawSender::Error::kOk);
-    msgs_sent++;
-    if (done) {
-      Exit();
+    // Send in bursts to reduce scheduler load to make the test more
+    // reproducible.
+    for (int i = 0; i < messages_per_ms * kRepeatOffset.count(); ++i) {
+      const bool done = (msgs_sent == queue_size + 1);
+      ASSERT_EQ(SendTestMessage(sender),
+                done ? RawSender::Error::kMessagesSentTooFast
+                     : RawSender::Error::kOk);
+      msgs_sent++;
+      if (done) {
+        Exit();
+        return;
+      }
     }
   });
 
-  const auto kRepeatOffset = std::chrono::milliseconds(1);
-  const auto base_offset = configuration::ChannelStorageDuration(
-                               event_loop->configuration(), sender.channel()) -
-                           (kRepeatOffset * (queue_size / 2));
   event_loop->OnRun([&event_loop, &timer, &base_offset, &kRepeatOffset]() {
     timer->Schedule(event_loop->monotonic_now() + base_offset, kRepeatOffset);
   });
@@ -3595,6 +3604,7 @@
 // situation
 TEST_P(AbstractEventLoopTest, SendingAfterSendingTooFast) {
   auto event_loop = MakePrimary();
+  event_loop->SetRuntimeRealtimePriority(5);
 
   auto sender = event_loop->MakeSender<TestMessage>("/test");