Bitcoin ABC  0.26.3
P2P Digital Currency
bench_bitcoin.cpp
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1 // Copyright (c) 2015-2019 The Bitcoin Core developers
2 // Distributed under the MIT software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4 
5 #include <bench/bench.h>
6 
7 #include <clientversion.h>
8 #include <common/args.h>
9 #include <crypto/sha256.h>
10 #include <util/fs.h>
11 #include <util/strencodings.h>
12 
13 #include <chrono>
14 #include <cstdint>
15 #include <iostream>
16 #include <sstream>
17 #include <vector>
18 
19 static const char *DEFAULT_BENCH_FILTER = ".*";
20 static constexpr int64_t DEFAULT_MIN_TIME_MS{10};
21 
22 static void SetupBenchArgs(ArgsManager &argsman) {
23  SetupHelpOptions(argsman);
24 
25  argsman.AddArg("-asymptote=<n1,n2,n3,...>",
26  "Test asymptotic growth of the runtime of an algorithm, if "
27  "supported by the benchmark",
29  argsman.AddArg("-filter=<regex>",
30  strprintf("Regular expression filter to select benchmark by "
31  "name (default: %s)",
34  argsman.AddArg("-list", "List benchmarks without executing them",
36  argsman.AddArg(
37  "-min_time=<milliseconds>",
38  strprintf(
39  "Minimum runtime per benchmark, in milliseconds (default: %d)",
42  argsman.AddArg(
43  "-output_csv=<output.csv>",
44  "Generate CSV file with the most important benchmark results",
46  argsman.AddArg("-output_json=<output.json>",
47  "Generate JSON file with all benchmark results",
49 }
50 
51 // parses a comma separated list like "10,20,30,50"
52 static std::vector<double> parseAsymptote(const std::string &str) {
53  std::stringstream ss(str);
54  std::vector<double> numbers;
55  double d;
56  char c;
57  while (ss >> d) {
58  numbers.push_back(d);
59  ss >> c;
60  }
61  return numbers;
62 }
63 
64 int main(int argc, char **argv) {
65  ArgsManager argsman;
66  SetupBenchArgs(argsman);
68  std::string error;
69  if (!argsman.ParseParameters(argc, argv, error)) {
70  tfm::format(std::cerr, "Error parsing command line arguments: %s\n",
71  error);
72  return EXIT_FAILURE;
73  }
74 
75  if (HelpRequested(argsman)) {
76  std::cout
77  << "Usage: bitcoin-bench [options]\n"
78  "\n"
79  << argsman.GetHelpMessage()
80  << "Description:\n"
81  "\n"
82  " bitcoin-bench executes microbenchmarks. The quality of the "
83  "benchmark results\n"
84  " highly depend on the stability of the machine. It can "
85  "sometimes be difficult\n"
86  " to get stable, repeatable results, so here are a few tips:\n"
87  "\n"
88  " * Use pyperf [1] to disable frequency scaling, turbo boost "
89  "etc. For best\n"
90  " results, use CPU pinning and CPU isolation (see [2]).\n"
91  "\n"
92  " * Each call of run() should do exactly the same work. E.g. "
93  "inserting into\n"
94  " a std::vector doesn't do that as it will reallocate on "
95  "certain calls. Make\n"
96  " sure each run has exactly the same preconditions.\n"
97  "\n"
98  " * If results are still not reliable, increase runtime with "
99  "e.g.\n"
100  " -min_time=5000 to let a benchmark run for at least 5 "
101  "seconds.\n"
102  "\n"
103  " * bitcoin-bench uses nanobench [3] for which there is "
104  "extensive\n"
105  " documentation available online.\n"
106  "\n"
107  "Environment Variables:\n"
108  "\n"
109  " To attach a profiler you can run a benchmark in endless "
110  "mode. This can be\n"
111  " done with the environment variable NANOBENCH_ENDLESS. E.g. "
112  "like so:\n"
113  "\n"
114  " NANOBENCH_ENDLESS=MuHash ./bitcoin-bench -filter=MuHash\n"
115  "\n"
116  " In rare cases it can be useful to suppress stability "
117  "warnings. This can be\n"
118  " done with the environment variable "
119  "NANOBENCH_SUPPRESS_WARNINGS, e.g:\n"
120  "\n"
121  " NANOBENCH_SUPPRESS_WARNINGS=1 ./bitcoin-bench\n"
122  "\n"
123  "Notes:\n"
124  "\n"
125  " 1. pyperf\n"
126  " https://github.com/psf/pyperf\n"
127  "\n"
128  " 2. CPU pinning & isolation\n"
129  " https://pyperf.readthedocs.io/en/latest/system.html\n"
130  "\n"
131  " 3. nanobench\n"
132  " https://github.com/martinus/nanobench\n"
133  "\n";
134 
135  return EXIT_SUCCESS;
136  }
137 
138  benchmark::Args args;
139  args.asymptote = parseAsymptote(argsman.GetArg("-asymptote", ""));
140  args.is_list_only = argsman.GetBoolArg("-list", false);
141  args.min_time = std::chrono::milliseconds(
142  argsman.GetIntArg("-min_time", DEFAULT_MIN_TIME_MS));
143  args.output_csv = argsman.GetPathArg("-output_csv");
144  args.output_json = argsman.GetPathArg("-output_json");
145  args.regex_filter = argsman.GetArg("-filter", DEFAULT_BENCH_FILTER);
146 
148 
149  return EXIT_SUCCESS;
150 }
bool HelpRequested(const ArgsManager &args)
Definition: args.cpp:732
void SetupHelpOptions(ArgsManager &args)
Add help options to the args manager.
Definition: args.cpp:737
static constexpr int64_t DEFAULT_MIN_TIME_MS
int main(int argc, char **argv)
static std::vector< double > parseAsymptote(const std::string &str)
static const char * DEFAULT_BENCH_FILTER
static void SetupBenchArgs(ArgsManager &argsman)
@ ALLOW_ANY
Definition: args.h:103
@ ALLOW_INT
Definition: args.h:101
@ ALLOW_BOOL
Definition: args.h:100
bool ParseParameters(int argc, const char *const argv[], std::string &error)
Definition: args.cpp:201
std::string GetHelpMessage() const
Get the help string.
Definition: args.cpp:653
int64_t GetIntArg(const std::string &strArg, int64_t nDefault) const
Return integer argument or default value.
Definition: args.cpp:526
std::string GetArg(const std::string &strArg, const std::string &strDefault) const
Return string argument or default value.
Definition: args.cpp:494
bool GetBoolArg(const std::string &strArg, bool fDefault) const
Return boolean argument or default value.
Definition: args.cpp:556
void AddArg(const std::string &name, const std::string &help, unsigned int flags, const OptionsCategory &cat)
Add argument.
Definition: args.cpp:620
fs::path GetPathArg(std::string arg, const fs::path &default_value={}) const
Return path argument or default value.
Definition: args.cpp:275
static void RunAll(const Args &args)
Definition: bench.cpp:51
bool error(const char *fmt, const Args &...args)
Definition: logging.h:226
void format(std::ostream &out, const char *fmt, const Args &...args)
Format list of arguments to the stream according to given format string.
Definition: tinyformat.h:1112
std::string SHA256AutoDetect()
Autodetect the best available SHA256 implementation.
Definition: sha256.cpp:746
std::string regex_filter
Definition: bench.h:50
fs::path output_json
Definition: bench.h:49
fs::path output_csv
Definition: bench.h:48
std::vector< double > asymptote
Definition: bench.h:47
std::chrono::milliseconds min_time
Definition: bench.h:46
bool is_list_only
Definition: bench.h:45
#define strprintf
Format arguments and return the string or write to given std::ostream (see tinyformat::format doc for...
Definition: tinyformat.h:1202