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#include <sys/time.h>
#include <iostream>
#include <fstream>
#include <cstdlib>
#include <stdint.h>
#include <cstring>
#include <vector>
#ifndef XXH3
#include "wyhash.h"
#else
#include "../xxHash/xxh3.h"
#endif
using namespace std;
struct ha{
size_t operator()(const string &s, uint64_t seed)const{
#ifndef XXH3
return wyhash(s.c_str(),s.size(),seed,_wyp);
#else
return XXH3_64bits_withSeed(s.c_str(),s.size(),seed);
#endif
}
};
vector<string> v;
template <class Hasher>
uint64_t bench_hash(const char *name){
Hasher h; string s; timeval beg, end;
uint64_t dummy=0; const uint64_t N=v.size(), R=0x1000;
cerr.precision(2); cerr.setf(ios::fixed); cerr<<'|'<<name<<(strlen(name)<8?"\t\t|":"\t|");
gettimeofday(&beg,NULL);
for(size_t r=0; r<R; r++) for(size_t i=0; i<N; i++) dummy+=h(v[i],r);
gettimeofday(&end,NULL);
cerr<<1e-6*R*N/(end.tv_sec-beg.tv_sec+1e-6*(end.tv_usec-beg.tv_usec))<<"\t\t|";
s.resize(1<<8);
gettimeofday(&beg,NULL);
for(size_t r=0; r<(R<<14); r++) dummy+=h(s,r);
gettimeofday(&end,NULL);
cerr<<1e-9*(R<<14)*s.size()/(end.tv_sec-beg.tv_sec+1e-6*(end.tv_usec-beg.tv_usec))<<"\t\t|";
s.resize(1<<16);
gettimeofday(&beg,NULL);
for(size_t r=0; r<(R<<6); r++) dummy+=h(s,r);
gettimeofday(&end,NULL);
cerr<<1e-9*(R<<6)*s.size()/(end.tv_sec-beg.tv_sec+1e-6*(end.tv_usec-beg.tv_usec))<<"\t\t|\n";
return dummy;
}
int main(void){
string file="/usr/share/dict/words", s;
ifstream fi(file.c_str());
for(fi>>s; !fi.eof(); fi>>s) if(s.size()) v.push_back(s);
fi.close();
//shuffle the array to benchmark random access
for(size_t i=v.size()-1; i; i--) swap(v[i],v[rand()%(i+1)]);
uint64_t r=0;
cerr<<file<<'\n';
cerr<<"|hash function\t|short hash/us\t|bulk_256B GB/s\t|bulk_64KB GB/s\t|\n";
cerr<<"|----\t\t|----\t\t|----\t\t|----\t\t|\n";
#ifndef XXH3
r+=bench_hash<ha>("wyhash");
#else
r+=bench_hash<ha>("xxh3");
#endif
return r;
}
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