[SDK] Invalid thread instrumentation in PeriodicExportingMetricReader (#3842)

Author: marcalff

CHANGELOG.md

@@ -54,6 +54,9 @@ Increment the:
 * [CONFIGURATION] File configuration - exemplar filter
   [#3837](https://github.com/open-telemetry/opentelemetry-cpp/pull/3837)
 
+* [SDK] Invalid thread instrumentation in PeriodicExportingMetricReader
+  [#3842](https://github.com/open-telemetry/opentelemetry-cpp/pull/3842)
+
 Breaking changes:
 
 * [CONFIGURATION] File configuration - remove zipkin
@@ -66,6 +69,13 @@ Breaking changes:
   * The Tls properties for Grpc and Http are renamed,
     due to an upstream schema change.
 
+* [SDK] Invalid thread instrumentation in PeriodicExportingMetricReader
+  [#3842](https://github.com/open-telemetry/opentelemetry-cpp/pull/3842)
+  * The collect thread in the periodic exporting metric reader no longer
+    exists.
+  * As a result, member `collect_thread_instrumentation` in class
+    `PeriodicExportingMetricReaderRuntimeOptions` is removed.
+
 ## [1.24 2025-11-20]
 
 * [RELEASE] Bump main branch to 1.24-dev

examples/otlp/http_instrumented_main.cc

@@ -229,10 +229,7 @@ void InitMetrics()
 #ifdef ENABLE_THREAD_INSTRUMENTATION_PREVIEW
   auto reader_periodic_instr = std::shared_ptr<opentelemetry::sdk::common::ThreadInstrumentation>(
       new MyThreadInstrumentation("PeriodicExportingMetricReader(periodic)", "", "medium"));
-  auto reader_collect_instr = std::shared_ptr<opentelemetry::sdk::common::ThreadInstrumentation>(
-      new MyThreadInstrumentation("PeriodicExportingMetricReader(collect)", "", "medium"));
   reader_rt_opts.periodic_thread_instrumentation = reader_periodic_instr;
-  reader_rt_opts.collect_thread_instrumentation  = reader_collect_instr;
 #endif /* ENABLE_THREAD_INSTRUMENTATION_PREVIEW */
   auto reader = opentelemetry::sdk::metrics::PeriodicExportingMetricReaderFactory::Create(
       std::move(exporter), reader_options, reader_rt_opts);

sdk/include/opentelemetry/sdk/metrics/export/periodic_exporting_metric_reader.h

@@ -62,7 +62,6 @@ class PeriodicExportingMetricReader : public MetricReader
 
   /* The background worker thread */
   std::shared_ptr<sdk::common::ThreadInstrumentation> worker_thread_instrumentation_;
-  std::shared_ptr<sdk::common::ThreadInstrumentation> collect_thread_instrumentation_;
   std::thread worker_thread_;
 };
 

sdk/include/opentelemetry/sdk/metrics/export/periodic_exporting_metric_reader_runtime_options.h

@@ -21,8 +21,6 @@ struct PeriodicExportingMetricReaderRuntimeOptions
 {
   std::shared_ptr<sdk::common::ThreadInstrumentation> periodic_thread_instrumentation =
       std::shared_ptr<sdk::common::ThreadInstrumentation>(nullptr);
-  std::shared_ptr<sdk::common::ThreadInstrumentation> collect_thread_instrumentation =
-      std::shared_ptr<sdk::common::ThreadInstrumentation>(nullptr);
 };
 
 }  // namespace metrics

sdk/src/metrics/export/periodic_exporting_metric_reader.cc

@@ -43,8 +43,7 @@ PeriodicExportingMetricReader::PeriodicExportingMetricReader(
     : exporter_{std::move(exporter)},
       export_interval_millis_{options.export_interval_millis},
       export_timeout_millis_{options.export_timeout_millis},
-      worker_thread_instrumentation_(nullptr),
-      collect_thread_instrumentation_(nullptr)
+      worker_thread_instrumentation_(nullptr)
 {
   if (export_interval_millis_ <= export_timeout_millis_)
   {
@@ -63,8 +62,7 @@ PeriodicExportingMetricReader::PeriodicExportingMetricReader(
     : exporter_{std::move(exporter)},
       export_interval_millis_{options.export_interval_millis},
       export_timeout_millis_{options.export_timeout_millis},
-      worker_thread_instrumentation_(runtime_options.periodic_thread_instrumentation),
-      collect_thread_instrumentation_(runtime_options.collect_thread_instrumentation)
+      worker_thread_instrumentation_(runtime_options.periodic_thread_instrumentation)
 {
   if (export_interval_millis_ <= export_timeout_millis_)
   {
@@ -161,13 +159,6 @@ bool PeriodicExportingMetricReader::CollectAndExportOnce()
   try
   {
 #endif
-#ifdef ENABLE_THREAD_INSTRUMENTATION_PREVIEW
-    if (collect_thread_instrumentation_ != nullptr)
-    {
-      collect_thread_instrumentation_->OnStart();
-      collect_thread_instrumentation_->BeforeLoad();
-    }
-#endif /* ENABLE_THREAD_INSTRUMENTATION_PREVIEW */
     auto start = std::chrono::steady_clock::now();
     this->Collect([this, &start](ResourceMetrics &metric_data) {
       auto end = std::chrono::steady_clock::now();
@@ -182,13 +173,6 @@ bool PeriodicExportingMetricReader::CollectAndExportOnce()
       return true;
     });
 
-#ifdef ENABLE_THREAD_INSTRUMENTATION_PREVIEW
-    if (collect_thread_instrumentation_ != nullptr)
-    {
-      collect_thread_instrumentation_->AfterLoad();
-      collect_thread_instrumentation_->OnEnd();
-    }
-#endif /* ENABLE_THREAD_INSTRUMENTATION_PREVIEW */
 #if OPENTELEMETRY_HAVE_EXCEPTIONS
   }
   catch (std::exception &e)