Remove epoll instances config

src/config.cpp

@@ -109,22 +109,13 @@ void ConfigParser::parse_server_config(const auto &toml_data,
     parse_field(srv, "max_request_size_bytes", config.max_request_size_bytes);
     parse_field(srv, "io_threads", config.io_threads);
 
-    // Set epoll_instances default to io_threads if not explicitly configured
-    bool epoll_instances_specified = srv.contains("epoll_instances");
-    if (!epoll_instances_specified) {
-      config.epoll_instances = config.io_threads;
-    } else {
-      parse_field(srv, "epoll_instances", config.epoll_instances);
-    }
+    // epoll_instances removed - now 1:1 with io_threads
 
     parse_field(srv, "event_batch_size", config.event_batch_size);
     parse_field(srv, "max_connections", config.max_connections);
     parse_field(srv, "read_buffer_size", config.read_buffer_size);
 
-    // Clamp epoll_instances to not exceed io_threads
-    if (config.epoll_instances > config.io_threads) {
-      config.epoll_instances = config.io_threads;
-    }
+    // epoll_instances validation removed - now always equals io_threads
   });
 }
 
@@ -213,15 +204,7 @@ bool ConfigParser::validate_config(const Config &config) {
     valid = false;
   }
 
-  if (config.server.epoll_instances < 1 ||
-      config.server.epoll_instances > config.server.io_threads) {
-    std::cerr
-        << "Configuration error: server.epoll_instances must be between 1 "
-           "and io_threads ("
-        << config.server.io_threads << "), got "
-        << config.server.epoll_instances << std::endl;
-    valid = false;
-  }
+  // epoll_instances validation removed - now always 1:1 with io_threads
 
   if (config.server.event_batch_size < 1 ||
       config.server.event_batch_size > 10000) {

src/config.hpp

@@ -40,10 +40,8 @@ struct ServerConfig {
   /// Maximum size in bytes for incoming HTTP requests (default: 1MB)
   int64_t max_request_size_bytes = 1024 * 1024;
   /// Number of I/O threads for handling connections and network events
+  /// Each I/O thread gets its own dedicated epoll instance
   int io_threads = 1;
-  /// Number of epoll instances to reduce epoll_ctl contention (default:
-  /// io_threads, max: io_threads)
-  int epoll_instances = 1;
   /// Event batch size for epoll processing
   int event_batch_size = 32;
   /// Maximum number of concurrent connections (0 = unlimited)

src/main.cpp

@@ -234,8 +234,7 @@ int main(int argc, char *argv[]) {
   std::cout << "Max request size: " << config->server.max_request_size_bytes
             << " bytes" << std::endl;
   std::cout << "I/O threads: " << config->server.io_threads << std::endl;
-  std::cout << "Epoll instances: " << config->server.epoll_instances
-            << std::endl;
+  std::cout << "Epoll instances: " << config->server.io_threads << std::endl;
   std::cout << "Event batch size: " << config->server.event_batch_size
             << std::endl;
   std::cout << "Max connections: " << config->server.max_connections

src/server.cpp

@@ -264,9 +264,9 @@ void Server::setup_shutdown_pipe() {
 
 void Server::create_epoll_instances() {
   // Create multiple epoll instances to reduce contention
-  epoll_fds_.resize(config_.server.epoll_instances);
+  epoll_fds_.resize(config_.server.io_threads);
 
-  for (int i = 0; i < config_.server.epoll_instances; ++i) {
+  for (int i = 0; i < config_.server.io_threads; ++i) {
     epoll_fds_[i] = epoll_create1(EPOLL_CLOEXEC);
     if (epoll_fds_[i] == -1) {
       perror("epoll_create1");

tests/test_server_connection_return.cpp

@@ -42,7 +42,6 @@ TEST_CASE(
     "Server correctly handles connection ownership transfer via pipeline") {
   weaseldb::Config config;
   config.server.io_threads = 1;
-  config.server.epoll_instances = 1;
 
   StaticThreadPipeline<Message, WaitStrategy::WaitIfStageEmpty, 1> pipeline{10};
   EchoHandler handler{pipeline};