Mongoose web server getting current working threads

Question

I am starting mongoose web server with x threads. Is there a way that I can log when all x threads are busy so I can increase the thread count if required ?

Answer 1

That is not possible without changing the code of Mongoose. I would, for example, change the static void worker_thread(struct mg_context *ctx) function in mongoose.c:

1. While the worker thread is inside the while loop while (consume_socket(ctx, &conn->client)), you could consider the worker thread as busy.
2. After close_connection(conn); the worker thread is free for processing a new event in the socket queue.

You can use that point for counting the number of busy threads.

Answer 2

As diewie suggested, you can:

• add "int num_idle" to the struct mg_context

• in consume_socket, do:

  ctx->num_idle++;
  
  // If the queue is empty, wait. We're idle at this point.
  while (ctx->sq_head == ctx->sq_tail && ctx->stop_flag == 0) {
    pthread_cond_wait(&ctx->sq_full, &ctx->mutex);
  }
  
  ctx->num_idle--;
  assert(ctx->num_idle >= 0);
  if (ctx->num_idle == 0) {
    ... your code ...
  }