1 files changed, 76 insertions, 0 deletions
diff --git a/src/collectors/apps.plugin/busy_threads.c b/src/collectors/apps.plugin/busy_threads.c
new file mode 100644
index 000000000..490c66148
--- /dev/null
+++ b/src/collectors/apps.plugin/busy_threads.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+/*
+ * A very simple pthreads program to spawn N busy threads.
+ * It is just used for validating apps.plugin CPU utilization
+ * calculations per operating system.
+ *
+ * Compile with:
+ *
+ * gcc -O2 -ggdb -o busy_threads busy_threads.c -pthread
+ *
+ * Run as:
+ *
+ * busy_threads 2
+ *
+ * The above will create 2 busy threads, each using 1 core in user time.
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <pthread.h>
+#include <signal.h>
+#include <unistd.h>
+
+volatile int keep_running = 1;
+
+void handle_signal(int signal) {
+    keep_running = 0;
+}
+
+void *busy_loop(void *arg) {
+    while (keep_running) {
+        // Busy loop to keep CPU at 100%
+    }
+    return NULL;
+}
+
+int main(int argc, char *argv[]) {
+    if (argc != 2) {
+        fprintf(stderr, "Usage: %s <number of threads>\n", argv[0]);
+        exit(EXIT_FAILURE);
+    }
+
+    int num_threads = atoi(argv[1]);
+    if (num_threads <= 0) {
+        fprintf(stderr, "Number of threads must be a positive integer.\n");
+        exit(EXIT_FAILURE);
+    }
+
+    // Register the signal handler to gracefully exit on Ctrl-C
+    signal(SIGINT, handle_signal);
+
+    pthread_t *threads = malloc(sizeof(pthread_t) * num_threads);
+    if (threads == NULL) {
+        perror("malloc");
+        exit(EXIT_FAILURE);
+    }
+
+    // Create threads
+    for (int i = 0; i < num_threads; i++) {
+        if (pthread_create(&threads[i], NULL, busy_loop, NULL) != 0) {
+            perror("pthread_create");
+            free(threads);
+            exit(EXIT_FAILURE);
+        }
+    }
+
+    // Wait for threads to finish (they never will unless interrupted)
+    for (int i = 0; i < num_threads; i++) {
+        pthread_join(threads[i], NULL);
+    }
+
+    free(threads);
+    return 0;
+}