YugabyteDB (2.13.0.0-b42, bfc6a6643e7399ac8a0e81d06a3ee6d6571b33ab)

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#ifndef YB_TABLET_OPERATIONS_OPERATION_TRACKER_H

#define YB_TABLET_OPERATIONS_OPERATION_TRACKER_H

#include <memory>

#include <string>

#include <unordered_map>

#include <vector>

#include "yb/gutil/ref_counted.h"

#include "yb/tablet/operations/operation.h"

#include "yb/util/locks.h"

#include "yb/util/opid.h"

namespace yb {

template<class T>

class AtomicGauge;

class Counter;

class MemTracker;

class MetricEntity;

namespace tablet {

class OperationDriver;

// Each TabletPeer has a OperationTracker which keeps track of pending operations.

// Each "LeaderOperation" will register itself by calling Add().

// It will remove itself by calling Release().

class OperationTracker {

 public:

  explicit OperationTracker(const std::string& log_prefix);

  ~OperationTracker();

  // Adds a operation to the set of tracked operations.

  //

  // In the event that the tracker's memory limit is exceeded, returns a

  // ServiceUnavailable status.

  CHECKED_STATUS Add(OperationDriver* driver);

  // Removes the operation from the pending list.

  // Also triggers the deletion of the Operation object, if its refcount == 0.

  void Release(OperationDriver* driver, OpIds* applied_op_ids);

  // Populates list of currently-running operations into 'pending_out' vector.

  std::vector<scoped_refptr<OperationDriver>> GetPendingOperations() const;

  // Returns number of pending operations.

  size_t TEST_GetNumPending() const;

  void WaitForAllToFinish() const;

  CHECKED_STATUS WaitForAllToFinish(const MonoDelta& timeout) const;

  void StartInstrumentation(const scoped_refptr<MetricEntity>& metric_entity);

  void StartMemoryTracking(const std::shared_ptr<MemTracker>& parent_mem_tracker);

  // Post tracker in called when operation tracker finishes tracking memory for corresponding op id.

  // So post tracker could start tracking this memory in case it is still keeping memory for this

  // op id.

  void SetPostTracker(std::function<void(const OpId&)> post_tracker) {

    post_tracker_ = std::move(post_tracker);

  }

  const std::string& LogPrefix() const {

    return log_prefix_;

  }

 private:

  struct Metrics {

    explicit Metrics(const scoped_refptr<MetricEntity>& entity);

    scoped_refptr<AtomicGauge<uint64_t> > all_operations_inflight;

    scoped_refptr<AtomicGauge<uint64_t> > operations_inflight[kOperationTypeMapSize];

    scoped_refptr<Counter> operation_memory_pressure_rejections;

  };

  // Increments relevant metric counters.

  void IncrementCounters(const OperationDriver& driver) const;

  // Decrements relevant metric counters.

  void DecrementCounters(const OperationDriver& driver) const;

  std::vector<scoped_refptr<OperationDriver>> GetPendingOperationsUnlocked() const REQUIRES(mutex_);

  const std::string log_prefix_;

  mutable std::mutex mutex_;

  mutable std::condition_variable cond_;

  // Per-operation state that is tracked along with the operation itself.

  struct State {

    // Approximate memory footprint of the operation.

    int64_t memory_footprint = 0;

  };

  // Protected by 'lock_'.

  typedef std::unordered_map<

      scoped_refptr<OperationDriver>,

      State,

      ScopedRefPtrHashFunctor,

      ScopedRefPtrEqualsFunctor> OperationMap;

  OperationMap pending_operations_ GUARDED_BY(mutex_);

  std::unique_ptr<Metrics> metrics_;

  std::shared_ptr<MemTracker> mem_tracker_;

  std::function<void(const OpId&)> post_tracker_;

  DISALLOW_COPY_AND_ASSIGN(OperationTracker);

};

}  // namespace tablet

}  // namespace yb

#endif // YB_TABLET_OPERATIONS_OPERATION_TRACKER_H