h2load: Explicitly count the number of requests left and inflight

src/h2load.cc

@@ -269,9 +269,7 @@ void conn_timeout_cb(EV_P_ ev_timer *w, int revents) {
 
 namespace {
 bool check_stop_client_request_timeout(Client *client, ev_timer *w) {
-  auto nreq = client->req_todo - client->req_started;
-
-  if (nreq == 0 ||
+  if (client->req_left == 0 ||
       client->streams.size() >= client->session->max_concurrent_streams()) {
     // no more requests to make, stop timer
     ev_timer_stop(client->worker->loop, w);
@@ -330,6 +328,8 @@ Client::Client(uint32_t id, Worker *worker, size_t req_todo)
       reqidx(0),
       state(CLIENT_IDLE),
       req_todo(req_todo),
+      req_left(req_todo),
+      req_inflight(0),
       req_started(0),
       req_done(0),
       id(id),
@@ -467,16 +467,13 @@ int Client::try_again_or_fail() {
 
   if (new_connection_requested) {
     new_connection_requested = false;
-    if (req_started < req_todo) {
+    if (req_left) {
       // At the moment, we don't have a facility to re-start request
       // already in in-flight.  Make them fail.
-      auto req_abandoned = req_started - req_done;
+      worker->stats.req_failed += req_inflight;
+      worker->stats.req_error += req_inflight;
 
-      worker->stats.req_failed += req_abandoned;
-      worker->stats.req_error += req_abandoned;
-      worker->stats.req_done += req_abandoned;
-
-      req_done = req_started;
+      req_inflight = 0;
 
       // Keep using current address
       if (connect() == 0) {
@@ -528,16 +525,18 @@ void Client::disconnect() {
 }
 
 int Client::submit_request() {
-  ++worker->stats.req_started;
   if (session->submit_request() != 0) {
     return -1;
   }
 
+  ++worker->stats.req_started;
+  --req_left;
   ++req_started;
+  ++req_inflight;
 
   // if an active timeout is set and this is the last request to be submitted
   // on this connection, start the active timeout.
-  if (worker->config->conn_active_timeout > 0. && req_started >= req_todo) {
+  if (worker->config->conn_active_timeout > 0. && req_left == 0) {
     ev_timer_start(worker->loop, &conn_active_watcher);
   }
 
@@ -551,34 +550,29 @@ void Client::process_timedout_streams() {
     }
   }
 
-  auto req_timed_out = req_todo - req_done;
-  worker->stats.req_timedout += req_timed_out;
+  worker->stats.req_timedout += req_inflight;
 
   process_abandoned_streams();
 }
 
 void Client::process_abandoned_streams() {
-  auto req_abandoned = req_todo - req_done;
+  auto req_abandoned = req_inflight + req_left;
 
   worker->stats.req_failed += req_abandoned;
   worker->stats.req_error += req_abandoned;
-  worker->stats.req_done += req_abandoned;
 
-  req_done = req_todo;
+  req_inflight = 0;
+  req_left = 0;
 }
 
 void Client::process_request_failure() {
-  auto req_abandoned = req_todo - req_started;
+  worker->stats.req_failed += req_left;
+  worker->stats.req_error += req_left;
 
-  worker->stats.req_failed += req_abandoned;
-  worker->stats.req_error += req_abandoned;
-  worker->stats.req_done += req_abandoned;
+  req_left = 0;
 
-  req_done += req_abandoned;
-
-  if (req_done == req_todo) {
+  if (req_inflight == 0) {
     terminate_session();
-    return;
   }
 }
 
@@ -711,6 +705,9 @@ void Client::on_status_code(int32_t stream_id, uint16_t status) {
 }
 
 void Client::on_stream_close(int32_t stream_id, bool success, bool final) {
+  ++req_done;
+  --req_inflight;
+
   auto req_stat = get_req_stat(stream_id);
   if (!req_stat) {
     return;
@@ -741,23 +738,19 @@ void Client::on_stream_close(int32_t stream_id, bool success, bool final) {
   }
 
   ++worker->stats.req_done;
-  ++req_done;
 
   worker->report_progress();
   streams.erase(stream_id);
-  if (req_done == req_todo) {
+  if (req_left == 0 && req_inflight == 0) {
     terminate_session();
     return;
   }
 
-  if (!config.timing_script && !final) {
-    if (req_started < req_todo) {
-      if (submit_request() != 0) {
+  if (!config.timing_script && !final && req_left > 0 &&
+      submit_request() != 0) {
     process_request_failure();
-      }
     return;
   }
-  }
 }
 
 RequestStat *Client::get_req_stat(int32_t stream_id) {
@@ -871,8 +864,7 @@ int Client::connection_made() {
   record_connect_time();
 
   if (!config.timing_script) {
-    auto nreq =
-        std::min(req_todo - req_started, session->max_concurrent_streams());
+    auto nreq = std::min(req_left, session->max_concurrent_streams());
     for (; nreq > 0; --nreq) {
       if (submit_request() != 0) {
         process_request_failure();

src/h2load.h

@@ -292,6 +292,11 @@ struct Client {
   ClientState state;
   // The number of requests this client has to issue.
   size_t req_todo;
+  // The number of requests left to issue
+  size_t req_left;
+  // The number of requests currently have started, but not abandoned
+  // or finished.
+  size_t req_inflight;
   // The number of requests this client has issued so far.
   size_t req_started;
   // The number of requests this client has done so far.

src/h2load_http1_session.cc

@@ -100,7 +100,7 @@ int htp_msg_completecb(http_parser *htp) {
     http_parser_pause(htp, 1);
     // Connection is going down.  If we have still request to do,
     // create new connection and keep on doing the job.
-    if (client->req_started < client->req_todo) {
+    if (client->req_left) {
       client->try_new_connection();
     }