jmap: a speed benchmark

ccan/jmap/tools/Makefile

@@ -0,0 +1,6 @@
+CFLAGS=-Wall -Werror -O3 -I../../..
+LDFLAGS=-lJudy
+
+speed: speed.o
+
+speed.o: speed.c ../jmap.h ../jmap_type.h ../jmap.c

ccan/jmap/tools/speed.c

@@ -0,0 +1,237 @@
+/* Simple speed tests for jmap. */
+#include <ccan/jmap/jmap_type.h>
+#include <ccan/jmap/jmap.c>
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/time.h>
+
+struct object {
+	/* Some contents. Doubles as consistency check. */
+	struct object *self;
+};
+
+/* 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;
+}
+
+JMAP_DEFINE_UINTIDX_TYPE(struct object, obj);
+
+int main(int argc, char *argv[])
+{
+	struct object *objs;
+	size_t i, j, num;
+	struct timeval start, stop;
+	struct jmap_obj *jmap;
+
+	num = argv[1] ? atoi(argv[1]) : 1000000;
+	objs = calloc(num, sizeof(objs[0]));
+
+	for (i = 0; i < num; i++) {
+		objs[i].self = &objs[i];
+	}
+
+	jmap = jmap_obj_new();
+
+	printf("Initial insert: ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++)
+		jmap_obj_add(jmap, i, objs[i].self);
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Initial lookup (match): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++)
+		if (jmap_obj_get(jmap, i)->self != objs[i].self)
+			abort();
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Initial lookup (miss): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++)
+		if (jmap_obj_get(jmap, i+num))
+			abort();
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	/* Lookups in order are very cache-friendly for judy; try random */
+	printf("Initial lookup (random): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0, j = 0; i < num; i++, j = (j + 10007) % num)
+		if (jmap_obj_get(jmap, j)->self != &objs[j])
+			abort();
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Initial delete all: ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++)
+		jmap_obj_del(jmap, i);
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Initial re-inserting: ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++)
+		jmap_obj_add(jmap, i, objs[i].self);
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Deleting first half: ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i+=2)
+		jmap_obj_del(jmap, i);
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Adding (a different) half: ");
+	fflush(stdout);
+
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i+=2)
+		jmap_obj_add(jmap, num+i, objs[i].self);
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Lookup after half-change (match): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 1; i < num; i+=2)
+		if (jmap_obj_get(jmap, i)->self != objs[i].self)
+			abort();
+	for (i = 0; i < num; i+=2)
+		if (jmap_obj_get(jmap, i+num)->self != objs[i].self)
+			abort();
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Lookup after half-change(miss): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++)
+		if (jmap_obj_get(jmap, i+num*2))
+			abort();
+	gettimeofday(&stop, NULL);
+	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("Details: churning first time\n");
+	for (i = 1; i < num; i+=2) {
+		if (!jmap_obj_del(jmap, i))
+			abort();
+		jmap_obj_add(jmap, i, objs[i].self);
+	}
+	for (i = 0; i < num; i+=2) {
+		if (!jmap_obj_del(jmap, i+num))
+			abort();
+		jmap_obj_add(jmap, i, objs[i].self);
+	}
+	for (i = 1; i < 5; i++) {
+		printf("Churning %s time: ",
+		       i == 1 ? "second"
+		       : i == 2 ? "third"
+		       : i == 3 ? "fourth"
+		       : "fifth");
+		fflush(stdout);
+		gettimeofday(&start, NULL);
+		for (j = 0; j < num; j++) {
+			if (!jmap_obj_del(jmap, num*(i-1)+j))
+				abort();
+			jmap_obj_add(jmap, num*i+j, &objs[j]);
+		}
+		gettimeofday(&stop, NULL);
+		printf(" %zu ns\n", normalize(&start, &stop, num));
+	}
+
+	/* Spread out the keys more to try to make it harder. */
+	printf("Details: reinserting with spread\n");
+	for (i = 0; i < num; i++) {
+		if (!jmap_obj_del(jmap, num*4 + i))
+			abort();
+		jmap_obj_add(jmap, num * 5 + i * 9, objs[i].self);
+	}
+
+	if (jmap_obj_popcount(jmap, 0, -1) != num)
+		abort();
+
+	printf("Lookup after churn & spread (match): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++)
+		if (jmap_obj_get(jmap, num * 5 + i * 9)->self != objs[i].self) {
+			printf("i  =%u\n", i);
+			abort();
+		}
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Lookup after churn & spread (miss): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++)
+		if (jmap_obj_get(jmap, num * 6 + i * 9))
+			abort();
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Lookup after churn & spread (random): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0, j = 0; i < num; i++, j = (j + 10007) % num)
+		if (jmap_obj_get(jmap, num * 5 + j * 9)->self != &objs[j])
+			abort();
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Lookup after churn & spread (half-random): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0, j = 0; i < num/2; i++, j = (j + 10007) % num) {
+		if (jmap_obj_get(jmap, num * 5 + j * 9)->self != &objs[j])
+			abort();
+		if (jmap_obj_get(jmap, num * 5 + (j + 1) * 9)->self != &objs[j+1])
+			abort();
+	}
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Deleting half after churn & spread: ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i+=2)
+		jmap_obj_del(jmap, num * 5 + i * 9);
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Adding (a different) half after churn & spread: ");
+	fflush(stdout);
+
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i+=2)
+		jmap_obj_add(jmap, num * 6 + i * 9, objs[i].self);
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	return 0;
+}