--- /dev/null
+/* Simple speed tests for a hash of strings. */
+#include <ccan/htable/htable_type.h>
+#include <ccan/htable/htable.c>
+#include <ccan/str_talloc/str_talloc.h>
+#include <ccan/grab_file/grab_file.h>
+#include <ccan/talloc/talloc.h>
+#include <ccan/hash/hash.h>
+#include <ccan/time/time.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/time.h>
+
+static size_t hashcount;
+
+static const char *strkey(const char *str)
+{
+ return str;
+}
+
+static size_t hash_str(const char *key)
+{
+ hashcount++;
+ return hash(key, strlen(key), 0);
+}
+
+static bool cmp(const char *obj, const char *key)
+{
+ return strcmp(obj, key) == 0;
+}
+
+HTABLE_DEFINE_TYPE(char, strkey, hash_str, cmp, str);
+
+/* Nanoseconds per operation */
+static size_t normalize(const struct timeval *start,
+ const struct timeval *stop,
+ unsigned int num)
+{
+ struct timeval diff;
+
+ timersub(stop, start, &diff);
+
+ /* Floating point is more accurate here. */
+ return (double)(diff.tv_sec * 1000000 + diff.tv_usec)
+ / num * 1000;
+}
+
+int main(int argc, char *argv[])
+{
+ size_t i, j, num;
+ struct timeval start, stop;
+ struct htable_str *ht;
+ char **words, **misswords;
+
+ words = strsplit(NULL, grab_file(NULL,
+ argv[1] ? argv[1] : "/usr/share/dict/words",
+ NULL), "\n");
+ ht = htable_str_new();
+ num = talloc_array_length(words) - 1;
+ printf("%zu words\n", num);
+
+ /* Append and prepend last char for miss testing. */
+ misswords = talloc_array(words, char *, num);
+ for (i = 0; i < num; i++) {
+ char lastc;
+ if (strlen(words[i]))
+ lastc = words[i][strlen(words[i])-1];
+ else
+ lastc = 'z';
+ misswords[i] = talloc_asprintf(misswords, "%c%s%c%c",
+ lastc, words[i], lastc, lastc);
+ }
+
+ printf("#01: Initial insert: ");
+ fflush(stdout);
+ start = time_now();
+ for (i = 0; i < num; i++)
+ htable_str_add(ht, words[i]);
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ printf("Bytes allocated: %zu\n",
+ sizeof(((struct htable *)ht)->table[0])
+ << ((struct htable *)ht)->bits);
+
+ printf("#02: Initial lookup (match): ");
+ fflush(stdout);
+ start = time_now();
+ for (i = 0; i < num; i++)
+ if (htable_str_get(ht, words[i]) != words[i])
+ abort();
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ printf("#03: Initial lookup (miss): ");
+ fflush(stdout);
+ start = time_now();
+ for (i = 0; i < num; i++) {
+ if (htable_str_get(ht, misswords[i]))
+ abort();
+ }
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ /* Lookups in order are very cache-friendly for judy; try random */
+ printf("#04: Initial lookup (random): ");
+ fflush(stdout);
+ start = time_now();
+ for (i = 0, j = 0; i < num; i++, j = (j + 10007) % num)
+ if (htable_str_get(ht, words[j]) != words[j])
+ abort();
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ hashcount = 0;
+ printf("#05: Initial delete all: ");
+ fflush(stdout);
+ start = time_now();
+ for (i = 0; i < num; i++)
+ if (!htable_str_del(ht, words[i]))
+ abort();
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ printf("#06: Initial re-inserting: ");
+ fflush(stdout);
+ start = time_now();
+ for (i = 0; i < num; i++)
+ htable_str_add(ht, words[i]);
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ hashcount = 0;
+ printf("#07: Deleting first half: ");
+ fflush(stdout);
+ start = time_now();
+ for (i = 0; i < num; i+=2)
+ if (!htable_str_del(ht, words[i]))
+ abort();
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ printf("#08: Adding (a different) half: ");
+ fflush(stdout);
+
+ start = time_now();
+ for (i = 0; i < num; i+=2)
+ htable_str_add(ht, misswords[i]);
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ printf("#09: Lookup after half-change (match): ");
+ fflush(stdout);
+ start = time_now();
+ for (i = 1; i < num; i+=2)
+ if (htable_str_get(ht, words[i]) != words[i])
+ abort();
+ for (i = 0; i < num; i+=2) {
+ if (htable_str_get(ht, misswords[i]) != misswords[i])
+ abort();
+ }
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ printf("#10: Lookup after half-change (miss): ");
+ fflush(stdout);
+ start = time_now();
+ for (i = 0; i < num; i+=2)
+ if (htable_str_get(ht, words[i]))
+ abort();
+ for (i = 1; i < num; i+=2) {
+ if (htable_str_get(ht, misswords[i]))
+ abort();
+ }
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ /* Hashtables with delete markers can fill with markers over time.
+ * so do some changes to see how it operates in long-term. */
+ printf("#11: Churn 1: ");
+ start = time_now();
+ for (j = 0; j < num; j+=2) {
+ if (!htable_str_del(ht, misswords[j]))
+ abort();
+ if (!htable_str_add(ht, words[j]))
+ abort();
+ }
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ printf("#12: Churn 2: ");
+ start = time_now();
+ for (j = 1; j < num; j+=2) {
+ if (!htable_str_del(ht, words[j]))
+ abort();
+ if (!htable_str_add(ht, misswords[j]))
+ abort();
+ }
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ printf("#13: Churn 3: ");
+ start = time_now();
+ for (j = 1; j < num; j+=2) {
+ if (!htable_str_del(ht, misswords[j]))
+ abort();
+ if (!htable_str_add(ht, words[j]))
+ abort();
+ }
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ /* Now it's back to normal... */
+ printf("#14: Post-Churn lookup (match): ");
+ fflush(stdout);
+ start = time_now();
+ for (i = 0; i < num; i++)
+ if (htable_str_get(ht, words[i]) != words[i])
+ abort();
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ printf("#15: Post-Churn lookup (miss): ");
+ fflush(stdout);
+ start = time_now();
+ for (i = 0; i < num; i++) {
+ if (htable_str_get(ht, misswords[i]))
+ abort();
+ }
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ /* Lookups in order are very cache-friendly for judy; try random */
+ printf("#16: Post-Churn lookup (random): ");
+ fflush(stdout);
+ start = time_now();
+ for (i = 0, j = 0; i < num; i++, j = (j + 10007) % num)
+ if (htable_str_get(ht, words[j]) != words[j])
+ abort();
+ stop = time_now();
+ printf(" %zu ns\n", normalize(&start, &stop, num));
+
+ return 0;
+}
projects / ccan / blobdiff