web: update web threads when openroad threads change

src/OpenRoad.cc

@@ -273,8 +273,7 @@ void OpenRoad::init(Tcl_Interp* tcl_interp,
   icewall_ = new pad::ICeWall(db_, logger_);
   dft_ = new dft::Dft(db_, sta_, logger_);
   example_ = new exa::Example(db_, logger_);
-  web_server_
-      = new web::WebServer(db_, sta_, logger_, tcl_interp, getThreadCount());
+  web_server_ = new web::WebServer(db_, sta_, logger_, tcl_interp);
 
   // Init components.
   Ord_Init(tcl_interp);
@@ -687,6 +686,9 @@ void OpenRoad::setThreadCount(int threads, bool print_info)
   if (global_router_ != nullptr) {
     global_router_->setNumThreads(threads_);
   }
+  if (web_server_ != nullptr) {
+    web_server_->setThreadCount(threads_);
+  }
 }
 
 void OpenRoad::setThreadCount(const char* threads, bool print_info)

src/web/include/web/web.h

@@ -72,8 +72,7 @@ class WebServer
   WebServer(odb::dbDatabase* db,
             sta::dbSta* sta,
             utl::Logger* logger,
-            Tcl_Interp* interp,
-            int num_threads);
+            Tcl_Interp* interp);
   ~WebServer();
 
   // Register the WebLogSink with the Logger so startup output is captured
@@ -84,6 +83,10 @@ class WebServer
   // the network threads racing the main thread's db construction.
   void initLogger();
 
+  // Sets the number of thread workers for the server's I/O context.
+  // Must be called before serve() to take effect.
+  void setThreadCount(int num_threads) { num_threads_ = num_threads; }
+
   // Start the web server on the given port.  Launches background
   // I/O threads and returns immediately.  A second call is a no-op if
   // the server is already running.

src/web/src/web.cpp

@@ -917,13 +917,8 @@ void Listener::on_accept(beast::error_code ec, Tcp::socket socket)
 WebServer::WebServer(odb::dbDatabase* db,
                      sta::dbSta* sta,
                      utl::Logger* logger,
-                     Tcl_Interp* interp,
-                     int num_threads)
-    : db_(db),
-      sta_(sta),
-      logger_(logger),
-      interp_(interp),
-      num_threads_(num_threads)
+                     Tcl_Interp* interp)
+    : db_(db), sta_(sta), logger_(logger), interp_(interp), num_threads_(1)
 {
 }
 

src/web/test/cpp/TestSaveReport.cpp

@@ -85,8 +85,7 @@ class SaveReportTest : public tst::Nangate45Fixture
     WebServer server(getDb(),
                      /*sta=*/nullptr,
                      getLogger(),
-                     /*interp=*/nullptr,
-                     /*num_threads=*/1);
+                     /*interp=*/nullptr);
     server.saveReport(path, max_setup, max_hold);
   }