csa_channel.h

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#ifndef MYSQL_CSA_SERVICE_CSA_CHANNEL_H
#define MYSQL_CSA_SERVICE_CSA_CHANNEL_H
 
#include <memory>
#include <ostream>
#include "mysql/scheduler/dependency_tracker_stub.h"
#include "mysql/scheduler/schedule_factory.h"
#include "mysql/scheduler/scheduler.h"
#include "mysql/scheduler/scheduler_clock.h"
#include "mysql/scheduler/thread_pool.h"
#include "sql/changestreams/apply/core/transaction_provider.h"
#include "sql/changestreams/apply/session/session_service.h"
 
namespace mysql::csa {
 
/// Aggregates applier structures for a single channel
struct Csa_channel {
  /// @brief Thread pool type for the scheduler
  using Thread_pool = scheduler::Thread_pool<scheduler::Task_result, 8192>;
  /// @brief Shared pointer to Thread_pool
  using Thread_pool_ptr = std::shared_ptr<Thread_pool>;
  /// @brief Shared pointer to Scheduler_clock
  using Clock_ptr = std::shared_ptr<scheduler::Scheduler_clock>;
  /// @brief Scheduler type
  using Scheduler_type = scheduler::Scheduler;
  /// @brief Shared pointer to Scheduler_type
  using Scheduler_ptr = std::shared_ptr<Scheduler_type>;
  /// @brief Schedule factory type
  using Schedule_factory = scheduler::Schedule_factory;
  /// @brief Shared pointer to Schedule_factory
  using Schedule_factory_ptr = std::shared_ptr<Schedule_factory>;
  /// @brief Shared pointer to Session_service
  using Session_service_ptr = std::shared_ptr<Session_service>;
 
  /// @brief Thread pool instance
  Thread_pool_ptr thread_pool;
  /// @brief Channel clock
  Clock_ptr scheduler_clock;
  /// @brief Channel commit order clock
  Clock_ptr commit_order_clock;
  /// @brief Session service - sessions contain channel information
  Session_service_ptr session_service;
  /// @brief Scheduler
  Scheduler_ptr scheduler;
  /// @brief Transaction provider for this channel
  Transaction_provider_sptr provider;
  /// Channel unique instance id
  std::size_t channel_instance_id;
  /// Channel THD
  THD *channel_thd;
  /// Stop channel flag, to avoid retries after applier stop
  std::atomic<bool> m_channel_stopped{false};
  /// Stop stop flag, when enabled, CSA won't kill ongoing sessions
  std::atomic<bool> m_soft_stop_enabled{false};
};
 
}  // namespace mysql::csa
 
#endif  // MYSQL_CSA_SERVICE_CSA_CHANNEL_H