chromium/third_party/perfetto/src/trace_processor/perfetto_sql/intrinsics/operators/counter_mipmap_operator.h

/*
 * Copyright (C) 2024 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
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#ifndef SRC_TRACE_PROCESSOR_PERFETTO_SQL_INTRINSICS_OPERATORS_COUNTER_MIPMAP_OPERATOR_H_
#define SRC_TRACE_PROCESSOR_PERFETTO_SQL_INTRINSICS_OPERATORS_COUNTER_MIPMAP_OPERATOR_H_

#include <sqlite3.h>
#include <cstdint>
#include <vector>

#include "src/trace_processor/containers/implicit_segment_forest.h"
#include "src/trace_processor/perfetto_sql/engine/perfetto_sql_engine.h"
#include "src/trace_processor/sqlite/bindings/sqlite_module.h"
#include "src/trace_processor/sqlite/module_lifecycle_manager.h"

namespace perfetto::trace_processor {

// Operator for building "mipmaps" [1] over the counter-like tracks.
//
// In the context of trace data, mipmap really means aggregating the counter
// values in a given time period into the {min, max, last} value for that
// period, allowing UIs to efficiently display the contents of a counter track
// when very zoomed out.
//
// Specifically, we are computing the query:
// ```
//   select
//     last_value(ts),
//     min(value),
//     max(value),
//     last_value(value)
//   from $input in
//   where in.ts_end >= $window_start and in.ts <= $window_end
//   group by ts / $window_resolution
//   order by ts
// ```
// but in O(logn) time by using a segment-tree like data structure (see
// ImplicitSegmentForest).
//
// [1] https://en.wikipedia.org/wiki/Mipmap
struct CounterMipmapOperator : sqlite::Module<CounterMipmapOperator> { … };

}  // namespace perfetto::trace_processor

#endif  // SRC_TRACE_PROCESSOR_PERFETTO_SQL_INTRINSICS_OPERATORS_COUNTER_MIPMAP_OPERATOR_H_