gperftools/benchmark/binary_trees.cc

109 lines
2.8 KiB
C++

// -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*-
//
// Copied from
// http://benchmarksgame.alioth.debian.org/u64q/program.php?test=binarytrees&lang=gpp&id=2
// and slightly modified (particularly by adding multi-threaded
// operation to hit malloc harder).
//
// This version of binary trees is mostly new/delete benchmark
//
// NOTE: copyright of this code is unclear, but we only distribute
// source.
/* The Computer Language Benchmarks Game
* http://benchmarksgame.alioth.debian.org/
*
* Contributed by Jon Harrop
* Modified by Alex Mizrahi
* Adapted for gperftools and added threads by Aliaksei Kandratsenka
*/
#include <algorithm>
#include <errno.h>
#include <iostream>
#include <pthread.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <vector>
struct Node {
Node *l, *r;
int i;
Node(int i2) : l(0), r(0), i(i2) {}
Node(Node *l2, int i2, Node *r2) : l(l2), r(r2), i(i2) {}
~Node() { delete l; delete r; }
int check() const {
if (l) {
return l->check() + i - r->check();
} else {
return i;
}
}
};
Node *make(int i, int d) {
if (d == 0) return new Node(i);
return new Node(make(2*i-1, d-1), i, make(2*i, d-1));
}
void run(int given_depth) {
int min_depth = 4,
max_depth = std::max(min_depth+2,
given_depth),
stretch_depth = max_depth+1;
{
Node *c = make(0, stretch_depth);
std::cout << "stretch tree of depth " << stretch_depth << "\t "
<< "check: " << c->check() << std::endl;
delete c;
}
Node *long_lived_tree=make(0, max_depth);
for (int d=min_depth; d<=max_depth; d+=2) {
int iterations = 1 << (max_depth - d + min_depth), c=0;
for (int i=1; i<=iterations; ++i) {
Node *a = make(i, d), *b = make(-i, d);
c += a->check() + b->check();
delete a;
delete b;
}
std::cout << (2*iterations) << "\t trees of depth " << d << "\t "
<< "check: " << c << std::endl;
}
std::cout << "long lived tree of depth " << max_depth << "\t "
<< "check: " << (long_lived_tree->check()) << "\n";
delete long_lived_tree;
}
static void *run_tramp(void *_a) {
intptr_t a = reinterpret_cast<intptr_t>(_a);
run(a);
return 0;
}
int main(int argc, char *argv[]) {
int given_depth = argc >= 2 ? atoi(argv[1]) : 20;
int thread_count = std::max(1, argc >= 3 ? atoi(argv[2]) : 1) - 1;
std::vector<pthread_t> threads(thread_count);
for (int i = 0; i < thread_count; i++) {
int rv = pthread_create(&threads[i], nullptr,
run_tramp,
reinterpret_cast<void *>(given_depth));
if (rv) {
errno = rv;
perror("pthread_create");
}
}
run_tramp(reinterpret_cast<void *>(given_depth));
for (int i = 0; i < thread_count; i++) {
pthread_join(threads[i], nullptr);
}
return 0;
}