You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
62 lines
2.2 KiB
62 lines
2.2 KiB
// Copyright 2013 The Chromium Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file.
|
|
|
|
#ifndef BASE_METRICS_HISTOGRAM_DELTA_SERIALIZATION_H_
|
|
#define BASE_METRICS_HISTOGRAM_DELTA_SERIALIZATION_H_
|
|
|
|
#include <memory>
|
|
#include <string>
|
|
#include <vector>
|
|
|
|
#include "base/base_export.h"
|
|
#include "base/macros.h"
|
|
#include "base/metrics/histogram_flattener.h"
|
|
#include "base/metrics/histogram_snapshot_manager.h"
|
|
#include "base/threading/thread_checker.h"
|
|
|
|
namespace base {
|
|
|
|
class HistogramBase;
|
|
|
|
// Serializes and restores histograms deltas.
|
|
class BASE_EXPORT HistogramDeltaSerialization : public HistogramFlattener {
|
|
public:
|
|
// |caller_name| is string used in histograms for counting inconsistencies.
|
|
explicit HistogramDeltaSerialization(const std::string& caller_name);
|
|
~HistogramDeltaSerialization() override;
|
|
|
|
// Computes deltas in histogram bucket counts relative to the previous call to
|
|
// this method. Stores the deltas in serialized form into |serialized_deltas|.
|
|
// If |serialized_deltas| is null, no data is serialized, though the next call
|
|
// will compute the deltas relative to this one. Setting |include_persistent|
|
|
// will include histograms held in persistent memory (and thus may be reported
|
|
// elsewhere); otherwise only histograms local to this process are serialized.
|
|
void PrepareAndSerializeDeltas(std::vector<std::string>* serialized_deltas,
|
|
bool include_persistent);
|
|
|
|
// Deserialize deltas and add samples to corresponding histograms, creating
|
|
// them if necessary. Silently ignores errors in |serialized_deltas|.
|
|
static void DeserializeAndAddSamples(
|
|
const std::vector<std::string>& serialized_deltas);
|
|
|
|
private:
|
|
// HistogramFlattener implementation.
|
|
void RecordDelta(const HistogramBase& histogram,
|
|
const HistogramSamples& snapshot) override;
|
|
|
|
ThreadChecker thread_checker_;
|
|
|
|
// Calculates deltas in histogram counters.
|
|
HistogramSnapshotManager histogram_snapshot_manager_;
|
|
|
|
// Output buffer for serialized deltas.
|
|
std::vector<std::string>* serialized_deltas_;
|
|
|
|
DISALLOW_COPY_AND_ASSIGN(HistogramDeltaSerialization);
|
|
};
|
|
|
|
} // namespace base
|
|
|
|
#endif // BASE_METRICS_HISTOGRAM_DELTA_SERIALIZATION_H_
|