foundationdb/fdbserver/LatencyBandsMap.actor.cpp

132 lines
4.7 KiB
C++

/*
* LatencyBandsMap.actor.cpp
*
* 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.
*/
#include "fdbserver/LatencyBandsMap.h"
#include "flow/UnitTest.h"
#include "flow/actorcompiler.h" // must be last include
class LatencyBandsMapImpl {
public:
ACTOR static Future<Void> expireOldTagsActor(LatencyBandsMap* self) {
loop {
wait(delay(5.0));
for (auto it = self->map.begin(); it != self->map.end();) {
const auto& [tag, expirableBands] = *it;
if (now() - expirableBands.lastUpdated > SERVER_KNOBS->GLOBAL_TAG_THROTTLING_TAG_EXPIRE_AFTER) {
CODE_PROBE(true, "LatencyBandsMap erasing expired tag");
it = self->map.erase(it);
} else {
++it;
}
}
}
}
};
LatencyBandsMap::ExpirableBands::ExpirableBands(LatencyBands&& bands)
: latencyBands(std::move(bands)), lastUpdated(now()) {}
Optional<LatencyBands*> LatencyBandsMap::getLatencyBands(TransactionTag tag) {
if (map.size() == maxSize && !map.count(tag)) {
CODE_PROBE(true, "LatencyBandsMap reached maxSize");
return {};
}
auto const [it, inserted] = map.try_emplace(
tag, LatencyBands(name, id, loggingInterval, [tag](auto& te) { te.detail("Tag", printable(tag)); }));
auto& expirableBands = it->second;
if (inserted) {
for (const auto& threshold : thresholds) {
expirableBands.latencyBands.addThreshold(threshold);
}
}
expirableBands.lastUpdated = now();
return &expirableBands.latencyBands;
}
LatencyBandsMap::LatencyBandsMap(std::string const& name, UID id, double loggingInterval, int maxSize)
: name(name), id(id), loggingInterval(loggingInterval), maxSize(maxSize) {
expireOldTags = LatencyBandsMapImpl::expireOldTagsActor(this);
}
void LatencyBandsMap::addMeasurement(TransactionTag tag, double value, int count) {
auto bands = getLatencyBands(tag);
if (bands.present()) {
bands.get()->addMeasurement(value, count);
}
}
void LatencyBandsMap::addThreshold(double value) {
thresholds.push_back(value);
for (auto& [tag, expirableBands] : map) {
expirableBands.latencyBands.addThreshold(value);
}
}
TEST_CASE("/fdbserver/LatencyBandsMap/Simple") {
state LatencyBandsMap latencyBandsMap("TestLatencyBandsMap", deterministicRandom()->randomUniqueID(), 10.0, 100);
state Standalone<VectorRef<TransactionTagRef>> tags;
tags.push_back_deep(tags.arena(), "a"_sr);
tags.push_back_deep(tags.arena(), "b"_sr);
tags.push_back_deep(tags.arena(), "c"_sr);
latencyBandsMap.addThreshold(0.1);
latencyBandsMap.addThreshold(0.2);
latencyBandsMap.addThreshold(0.4);
state int measurements = 0;
loop {
wait(delayJittered(0.1));
auto const tag = deterministicRandom()->randomChoice(tags);
latencyBandsMap.addMeasurement(tag, deterministicRandom()->random01());
if (++measurements == 1000) {
return Void();
}
}
}
TEST_CASE("/fdbserver/LatencyBandsMap/MaxSize") {
LatencyBandsMap latencyBandsMap("TestLatencyBandsMap", deterministicRandom()->randomUniqueID(), 10.0, 2);
latencyBandsMap.addMeasurement("a"_sr, deterministicRandom()->random01());
latencyBandsMap.addMeasurement("b"_sr, deterministicRandom()->random01());
latencyBandsMap.addMeasurement("c"_sr, deterministicRandom()->random01());
ASSERT_EQ(latencyBandsMap.size(), 2);
return Void();
}
TEST_CASE("/fdbserver/LatencyBandsMap/Expire") {
state LatencyBandsMap latencyBandsMap("TestLatencyBandsMap", deterministicRandom()->randomUniqueID(), 10.0, 100);
latencyBandsMap.addMeasurement("a"_sr, deterministicRandom()->random01());
latencyBandsMap.addMeasurement("b"_sr, deterministicRandom()->random01());
latencyBandsMap.addMeasurement("c"_sr, deterministicRandom()->random01());
latencyBandsMap.addThreshold(0.1);
latencyBandsMap.addThreshold(0.2);
latencyBandsMap.addThreshold(0.4);
ASSERT_EQ(latencyBandsMap.size(), 3);
state int waitIterations = 0;
loop {
wait(delay(1.0));
latencyBandsMap.addMeasurement("a"_sr, deterministicRandom()->random01());
latencyBandsMap.addMeasurement("b"_sr, deterministicRandom()->random01());
if (++waitIterations == 2 * SERVER_KNOBS->GLOBAL_TAG_THROTTLING_TAG_EXPIRE_AFTER) {
break;
}
}
ASSERT_EQ(latencyBandsMap.size(), 2);
return Void();
}