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#include <stdlib.h> /* malloc */
#include <sys/time.h> /* gettimeofday */
#include <errno.h> /* perror */
#include <stdio.h> /* printf */
#include "uthash.h"
#define BUFLEN 20
#if 0
#undef uthash_expand_fyi
#define uthash_expand_fyi(tbl) printf("expanding to %d buckets\n", tbl->num_buckets)
#endif
typedef struct name_rec {
char boy_name[BUFLEN];
UT_hash_handle hh;
} name_rec;
int main(int argc,char *argv[])
{
name_rec *name, *names=NULL;
char linebuf[BUFLEN];
FILE *file;
int i=0,j,nloops=3,loopnum=0,miss;
struct timeval tv1,tv2;
long elapsed_usec;
if (argc > 1) {
nloops = atoi(argv[1]);
}
if ( (file = fopen( "test14.dat", "r" )) == NULL ) {
perror("can't open: ");
exit(-1);
}
while (fgets(linebuf,BUFLEN,file) != NULL) {
i++;
if ( (name = (name_rec*)malloc(sizeof(name_rec))) == NULL) {
exit(-1);
}
strcpy(name->boy_name, linebuf);
HASH_ADD_STR(names,boy_name,name);
}
again:
if (fseek(file,0,SEEK_SET) == -1) {
fprintf(stderr,"fseek failed: %s\n", strerror(errno));
}
j=0;
if (gettimeofday(&tv1,NULL) == -1) {
perror("gettimeofday: ");
}
while (fgets(linebuf,BUFLEN,file) != NULL) {
/* if we do 10 loops, the first has a 0% miss rate,
* the second has a 10% miss rate, etc */
miss = ((rand()*1.0/RAND_MAX) < (loopnum*1.0/nloops)) ? 1 : 0;
/* generate a miss if we want one */
if (miss) {
linebuf[0]++;
if (linebuf[1] != '\0') {
linebuf[1]++;
}
}
HASH_FIND_STR(names,linebuf,name);
if (name) {
j++;
}
}
if (gettimeofday(&tv2,NULL) == -1) {
perror("gettimeofday: ");
}
elapsed_usec = ((tv2.tv_sec - tv1.tv_sec) * 1000000) + (tv2.tv_usec - tv1.tv_usec);
printf("lookup on %d of %d (%.2f%%) names succeeded (%.2f usec)\n", j, i,
j*100.0/i, (double)(elapsed_usec));
if (++loopnum < nloops) {
goto again;
}
fclose(file);
return 0;
}
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