1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
|
// Copyright 2022 The Abseil 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
//
// https://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 <algorithm>
#include <atomic>
#include <cstddef>
#include <cstring>
#include <memory>
#include <new>
#include <random>
#include <string>
#include <type_traits>
#include <utility>
#include <vector>
#include "absl/base/config.h"
#include "absl/container/internal/layout.h"
#include "absl/log/vlog_config.h"
#include "absl/memory/memory.h"
#include "absl/random/distributions.h"
#include "absl/strings/str_cat.h"
#include "benchmark/benchmark.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace log_internal {
// Performance of `UpdateLogSites` depends upon the number and organization of
// `VLogSite`s in the program. We can synthesize some on the heap to mimic
// their layout and linkage in static data.
class SyntheticBinary {
public:
explicit SyntheticBinary(const size_t num_tus,
const size_t max_extra_static_data_bytes_per_tu,
const size_t max_sites_per_tu,
const int num_shuffles) {
per_tu_data_.reserve(num_tus);
auto sites = absl::make_unique<VLogSite *[]>(num_tus * max_sites_per_tu);
for (size_t i = 0; i < num_tus; i++) {
const std::string filename =
absl::StrCat("directory-", i / 100, "/subdirectory-", i % 100 / 10,
"/file-", i % 10, ".cc");
container_internal::Layout<char, VLogSite, char> layout(
filename.size() + 1,
absl::LogUniform<size_t>(bitgen_, 1, max_sites_per_tu),
absl::LogUniform<size_t>(bitgen_, 0,
max_extra_static_data_bytes_per_tu));
auto buf = absl::make_unique<char[]>(layout.AllocSize());
layout.PoisonPadding(buf.get());
memcpy(layout.Pointer<0>(buf.get()), filename.c_str(),
filename.size() + 1);
for (VLogSite &site : layout.Slice<1>(buf.get())) {
sites[num_sites_++] =
new (&site) VLogSite(layout.Pointer<0>(buf.get()));
// The last one is a dangling pointer but will be fixed below.
site.next_.store(&site + 1, std::memory_order_seq_cst);
}
num_extra_static_data_bytes_ += layout.Size<2>();
per_tu_data_.push_back(PerTU{layout, std::move(buf)});
}
// Now link the files together back-to-front into a circular list.
for (size_t i = 0; i < num_tus; i++) {
auto &tu = per_tu_data_[i];
auto &next_tu = per_tu_data_[(i + 1) % num_tus];
tu.layout.Slice<1>(tu.buf.get())
.back()
.next_.store(next_tu.layout.Pointer<1>(next_tu.buf.get()),
std::memory_order_seq_cst);
}
// Now do some shufflin'.
auto new_sites = absl::make_unique<VLogSite *[]>(num_sites_);
for (int shuffle_num = 0; shuffle_num < num_shuffles; shuffle_num++) {
// Each shuffle cuts the ring into three pieces and rearranges them.
const size_t cut_a = absl::Uniform(bitgen_, size_t{0}, num_sites_);
const size_t cut_b = absl::Uniform(bitgen_, size_t{0}, num_sites_);
const size_t cut_c = absl::Uniform(bitgen_, size_t{0}, num_sites_);
if (cut_a == cut_b || cut_b == cut_c || cut_a == cut_c) continue;
// The same cuts, sorted:
const size_t cut_1 = std::min({cut_a, cut_b, cut_c});
const size_t cut_3 = std::max({cut_a, cut_b, cut_c});
const size_t cut_2 = cut_a ^ cut_b ^ cut_c ^ cut_1 ^ cut_3;
VLogSite *const tmp = sites[cut_1]->next_.load(std::memory_order_seq_cst);
sites[cut_1]->next_.store(
sites[cut_2]->next_.load(std::memory_order_seq_cst),
std::memory_order_seq_cst);
sites[cut_2]->next_.store(
sites[cut_3]->next_.load(std::memory_order_seq_cst),
std::memory_order_seq_cst);
sites[cut_3]->next_.store(tmp, std::memory_order_seq_cst);
memcpy(&new_sites[0], &sites[0], sizeof(VLogSite *) * (cut_1 + 1));
memcpy(&new_sites[cut_1 + 1], &sites[cut_2 + 1],
sizeof(VLogSite *) * (cut_3 - cut_2));
memcpy(&new_sites[cut_1 + 1 + cut_3 - cut_2], &sites[cut_1 + 1],
sizeof(VLogSite *) * (cut_2 - cut_1));
memcpy(&new_sites[cut_3 + 1], &sites[cut_3 + 1],
sizeof(VLogSite *) * (num_sites_ - cut_3 - 1));
sites.swap(new_sites);
}
const char *last_file = nullptr;
for (size_t i = 0; i < num_sites_; i++) {
if (sites[i]->file_ == last_file) continue;
last_file = sites[i]->file_;
num_new_files_++;
}
absl::log_internal::SetVModuleListHeadForTestOnly(sites[0]);
sites[num_tus - 1]->next_.store(nullptr, std::memory_order_seq_cst);
}
~SyntheticBinary() {
static_assert(std::is_trivially_destructible<VLogSite>::value, "");
absl::log_internal::SetVModuleListHeadForTestOnly(nullptr);
}
size_t num_sites() const { return num_sites_; }
size_t num_new_files() const { return num_new_files_; }
size_t num_extra_static_data_bytes() const {
return num_extra_static_data_bytes_;
}
private:
struct PerTU {
container_internal::Layout<char, VLogSite, char> layout;
std::unique_ptr<char[]> buf;
};
std::mt19937 bitgen_;
std::vector<PerTU> per_tu_data_;
size_t num_sites_ = 0;
size_t num_new_files_ = 0;
size_t num_extra_static_data_bytes_ = 0;
};
namespace {
void BM_UpdateVModuleEmpty(benchmark::State& state) {
SyntheticBinary bin(static_cast<size_t>(state.range(0)), 10 * 1024 * 1024,
256, state.range(1));
for (auto s : state) {
absl::log_internal::UpdateVModule("");
}
state.SetItemsProcessed(static_cast<int>(bin.num_new_files()));
}
BENCHMARK(BM_UpdateVModuleEmpty)
->ArgPair(100, 200)
->ArgPair(1000, 2000)
->ArgPair(10000, 20000);
void BM_UpdateVModuleShort(benchmark::State& state) {
SyntheticBinary bin(static_cast<size_t>(state.range(0)), 10 * 1024 * 1024,
256, state.range(1));
for (auto s : state) {
absl::log_internal::UpdateVModule("directory2/*=4");
}
state.SetItemsProcessed(static_cast<int>(bin.num_new_files()));
}
BENCHMARK(BM_UpdateVModuleShort)
->ArgPair(100, 200)
->ArgPair(1000, 2000)
->ArgPair(10000, 20000);
void BM_UpdateVModuleLong(benchmark::State& state) {
SyntheticBinary bin(static_cast<size_t>(state.range(0)), 10 * 1024 * 1024,
256, state.range(1));
for (auto s : state) {
absl::log_internal::UpdateVModule(
"d?r?c?o?y2/*=4,d?*r?*c?**o?*y1/*=2,d?*rc?**o?*y3/*=2,,"
"d?*r?*c?**o?*1/*=1,d?*r?**o?*y1/*=2,d?*r???***y1/*=7,"
"d?*r?**o?*y1/aaa=6");
}
state.SetItemsProcessed(static_cast<int>(bin.num_new_files()));
}
BENCHMARK(BM_UpdateVModuleLong)
->ArgPair(100, 200)
->ArgPair(1000, 2000)
->ArgPair(10000, 20000);
} // namespace
} // namespace log_internal
ABSL_NAMESPACE_END
} // namespace absl
|
