foundationdb/flow/Tracing.h

124 lines
3.6 KiB
C++

/*
* Tracing.h
*
* This source file is part of the FoundationDB open source project
*
* Copyright 2013-2020 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/FDBTypes.h"
#include "flow/IRandom.h"
#include <unordered_set>
#include <atomic>
struct Location {
StringRef name;
};
inline Location operator"" _loc(const char* str, size_t size) {
return Location{ StringRef(reinterpret_cast<const uint8_t*>(str), size) };
}
struct Span {
Span(SpanID context, Location location, std::initializer_list<SpanID> const& parents = {})
: context(context), begin(g_network->now()), location(location), parents(arena, parents.begin(), parents.end()) {
if (parents.size() > 0) {
this->context = SpanID((*parents.begin()).first(), context.second());
}
}
Span(Location location, std::initializer_list<SpanID> const& parents = {})
: Span(deterministicRandom()->randomUniqueID(), location, parents) {}
Span(Location location, SpanID context) : Span(location, { context }) {}
Span(const Span&) = delete;
Span(Span&& o) {
arena = std::move(o.arena);
context = o.context;
begin = o.begin;
end = o.end;
location = o.location;
parents = std::move(o.parents);
o.context = UID();
o.begin = 0.0;
o.end = 0.0;
}
Span() {}
~Span();
Span& operator=(Span&& o);
Span& operator=(const Span&) = delete;
void swap(Span& other) {
std::swap(arena, other.arena);
std::swap(context, other.context);
std::swap(begin, other.begin);
std::swap(end, other.end);
std::swap(location, other.location);
std::swap(parents, other.parents);
}
void addParent(SpanID span) {
if (parents.size() == 0) {
// Use first parent to set trace ID. This is non-ideal for spans
// with multiple parents, because the trace ID will associate the
// span with only one trace. A workaround is to look at the parent
// relationships instead of the trace ID. Another option in the
// future is to keep a list of trace IDs.
context = SpanID(span.first(), context.second());
}
parents.push_back(arena, span);
}
void addTag(const std::string& key, const std::string value) {
tags[key] = value;
}
Arena arena;
UID context = UID();
double begin = 0.0, end = 0.0;
Location location;
SmallVectorRef<SpanID> parents;
std::unordered_map<std::string, std::string> tags;
};
enum class TracerType {
DISABLED = 0,
LOG_FILE = 1,
NETWORK_ASYNC = 2,
NETWORK_LOSSY = 3,
END = 4
};
struct ITracer {
virtual ~ITracer();
virtual TracerType type() const = 0;
// passed ownership to the tracer
virtual void trace(Span const& span) = 0;
};
void openTracer(TracerType type);
template <class T>
struct SpannedDeque : Deque<T> {
Span span;
explicit SpannedDeque(Location loc) : span(deterministicRandom()->randomUniqueID(), loc) {}
SpannedDeque(SpannedDeque&& other) : Deque<T>(std::move(other)), span(std::move(other.span)) {}
SpannedDeque(SpannedDeque const&) = delete;
SpannedDeque& operator=(SpannedDeque const&) = delete;
SpannedDeque& operator=(SpannedDeque&& other) {
*static_cast<Deque<T>*>(this) = std::move(other);
span = std::move(other.span);
}
};