foundationdb/fdbserver/TransactionTagCounter.h

69 lines
2.3 KiB
C++

/*
* TransactionTagCounter.h
*
* This source file is part of the FoundationDB open source project
*
* Copyright 2013-2022 Apple Inc. and the FoundationDB project authors
*
* 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
* limitations under the License.
*/
#pragma once
#include "fdbclient/StorageServerInterface.h"
#include "fdbclient/TagThrottle.actor.h"
#include "fdbserver/Knobs.h"
class TopKTags {
public:
struct TagAndCount {
TransactionTag tag;
int64_t count;
bool operator<(TagAndCount const& other) const { return count < other.count; }
explicit TagAndCount(TransactionTag tag, int64_t count) : tag(tag), count(count) {}
};
private:
// Because the number of tracked is expected to be small, they can be tracked
// in a simple vector. If the number of tracked tags increases, a more sophisticated
// data structure will be required.
std::vector<TagAndCount> topTags;
int limit;
public:
explicit TopKTags(int limit) : limit(limit) { ASSERT_GT(limit, 0); }
void incrementTagCount(TransactionTag tag, int previousCount, int increase);
std::vector<StorageQueuingMetricsReply::TagInfo> getBusiestTags(double elapsed, double totalSampleCount) const;
void clear() { topTags.clear(); }
};
class TransactionTagCounter {
UID thisServerID;
TransactionTagMap<int64_t> intervalCounts;
int64_t intervalTotalSampledCount = 0;
TopKTags topTags;
double intervalStart = 0;
std::vector<StorageQueuingMetricsReply::TagInfo> previousBusiestTags;
Reference<EventCacheHolder> busiestReadTagEventHolder;
public:
TransactionTagCounter(UID thisServerID);
static int64_t costFunction(int64_t bytes) { return bytes / SERVER_KNOBS->READ_COST_BYTE_FACTOR + 1; }
void addRequest(Optional<TagSet> const& tags, int64_t bytes);
void startNewInterval();
std::vector<StorageQueuingMetricsReply::TagInfo> const& getBusiestTags() const { return previousBusiestTags; }
};