lib/ccan/htable, strset: benchmarking tools.

This lets us compare hash table vs. strset vs. the example
implementation of critbit trees.

cbspeed 100 runs, min-max(avg):
#01: Initial insert:   236-245(237)
#02: Initial lookup (match):   180-186(180)
#03: Initial lookup (miss):   171-185(172)
#04: Initial lookup (random):   441-457(444)
#05: Initial delete all:   127-132(128)
#06: Initial re-inserting:   219-225(220)
#07: Deleting first half:   101-104(102)
#08: Adding (a different) half:   158-162(159)
#09: Lookup after half-change (match):   202-207(203)
#10: Lookup after half-change (miss):   217-222(218)
#11: Churn 1:   297-302(299)
#12: Churn 2:   297-305(300)
#13: Churn 3:   301-308(303)
#14: Post-Churn lookup (match):   189-195(190)
#15: Post-Churn lookup (miss):   189-193(190)
#16: Post-Churn lookup (random):   499-513(503)

speed 100 runs, min-max(avg):
#01: Initial insert:   211-218(212)
#02: Initial lookup (match):   161-166(162)
#03: Initial lookup (miss):   157-162(158)
#04: Initial lookup (random):   452-460(454)
#05: Initial delete all:   126-135(127)
#06: Initial re-inserting:   193-201(194)
#07: Deleting first half:   99-107(99)
#08: Adding (a different) half:   143-190(144)
#09: Lookup after half-change (match):   183-195(184)
#10: Lookup after half-change (miss):   197-203(198)
#11: Churn 1:   271-278(274)
#12: Churn 2:   280-287(282)
#13: Churn 3:   277-285(279)
#14: Post-Churn lookup (match):   171-175(171)
#15: Post-Churn lookup (miss):   174-178(175)
#16: Post-Churn lookup (random):   525-552(528)

stringspeed 100 runs, min-max(avg):
#01: Initial insert:   300-343(308)
#02: Initial lookup (match):   98-136(99)
#03: Initial lookup (miss):   73-102(75)
#04: Initial lookup (random):   230-282(233)
#05: Initial delete all:   66-102(69)
#06: Initial re-inserting:   62-99(64)
#07: Deleting first half:   43-52(43)
#08: Adding (a different) half:   101-156(106)
#09: Lookup after half-change (match):   114-156(120)
#10: Lookup after half-change (miss):   94-103(95)
#11: Churn 1:   98-105(99)
#12: Churn 2:   96-104(98)
#13: Churn 3:   174-184(176)
#14: Post-Churn lookup (match):   93-112(94)
#15: Post-Churn lookup (miss):   77-107(79)
#16: Post-Churn lookup (random):   229-265(232)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
(Imported from CCAN commit 5c559e7df1d31b4c0ddf26451fac972dc8a0c2c9)

5 files changed, 1104 insertions, 1 deletions

diff --git a/lib/ccan/htable/tools/Makefile b/lib/ccan/htable/tools/Makefile
index 001e160b78..289d92b335 100644
--- a/lib/ccan/htable/tools/Makefile
+++ b/lib/ccan/htable/tools/Makefile
@@ -1,5 +1,18 @@
 CFLAGS=-Wall -Werror -O3 -I../../..
+#CFLAGS=-Wall -Werror -g -I../../..
 
-speed: speed.o ../../hash.o
+all: speed stringspeed
+
+speed: speed.o hash.o
 
 speed.o: speed.c ../htable.h ../htable.c
+
+hash.o: ../../hash/hash.c
+	$(CC) $(CFLAGS) -c -o $@ $<
+
+stringspeed: stringspeed.o hash.o ../../talloc.o ../../str_talloc.o ../../grab_file.o ../../str.o ../../time.o ../../noerr.o
+
+stringspeed.o: speed.c ../htable.h ../htable.c
+
+clean:
+	rm -f stringspeed speed
diff --git a/lib/ccan/htable/tools/stringspeed.c b/lib/ccan/htable/tools/stringspeed.c
new file mode 100644
index 0000000000..00ad2790cd
--- /dev/null
+++ b/lib/ccan/htable/tools/stringspeed.c
@@ -0,0 +1,246 @@
+/* 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;
+}
diff --git a/lib/ccan/strset/tools/Makefile b/lib/ccan/strset/tools/Makefile
new file mode 100644
index 0000000000..77b1f7d709
--- /dev/null
+++ b/lib/ccan/strset/tools/Makefile
@@ -0,0 +1,11 @@
+CFLAGS=-Wall -Werror -O3 -I../../..
+#CFLAGS=-Wall -Werror -g -I../../..
+
+all: cbspeed speed
+
+cbspeed: cbspeed.o ../../talloc.o ../../str_talloc.o ../../grab_file.o ../../str.o ../../time.o ../../noerr.o
+
+speed: speed.o ../../talloc.o ../../str_talloc.o ../../grab_file.o ../../str.o ../../time.o ../../noerr.o
+
+clean:
+	rm -f cbspeed speed speed.o cbspeed.o
diff --git a/lib/ccan/strset/tools/cbspeed.c b/lib/ccan/strset/tools/cbspeed.c
new file mode 100644
index 0000000000..a176649034
--- /dev/null
+++ b/lib/ccan/strset/tools/cbspeed.c
@@ -0,0 +1,590 @@
+/* Simple speed tests using original critbit code (modified not to allocate).
+ *
+ * Results on my 32 bit Intel(R) Core(TM) i5 CPU M 560  @ 2.67GHz, gcc 4.5.2:
+ * Run 100 times: Min-Max(Avg)
+ #01: Initial insert:   237-257(239)
+ #02: Initial lookup (match):   180-197(181)
+ #03: Initial lookup (miss):   171-190(172)
+ #04: Initial lookup (random):   441-455(446)
+ #05: Initial delete all:   127-148(128)
+ #06: Initial re-inserting:   219-298(221)
+ #07: Deleting first half:   101-109(102)
+ #08: Adding (a different) half:   159-165(160)
+ #09: Lookup after half-change (match):   203-216(204)
+ #10: Lookup after half-change (miss):   217-225(218)
+ #11: Churn 1:   298-311(300)
+ #12: Churn 2:   298-318(301)
+ #13: Churn 3:   301-322(304)
+ #14: Post-Churn lookup (match):   189-196(190)
+ #15: Post-Churn lookup (miss):   189-197(191)
+ #16: Post-Churn lookup (random):   500-531(506)
+ */
+#include <ccan/str_talloc/str_talloc.h>
+#include <ccan/grab_file/grab_file.h>
+#include <ccan/talloc/talloc.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>
+
+/* CRITBIT source */
+typedef struct {
+  void *root;
+} critbit0_tree;
+
+int critbit0_contains(critbit0_tree *t, const char *u);
+int critbit0_insert(critbit0_tree *t, const char *u);
+int critbit0_delete(critbit0_tree *t, const char *u);
+void critbit0_clear(critbit0_tree *t);
+int critbit0_allprefixed(critbit0_tree *t, const char *prefix,
+                         int (*handle) (const char *, void *), void *arg);
+
+#define uint8 uint8_t
+#define uint32 uint32_t
+
+static size_t allocated;
+
+/*2:*/
+
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include <sys/types.h>
+#include <errno.h>
+
+typedef struct{
+void*child[2];
+uint32 byte;
+uint8 otherbits;
+}critbit0_node;
+
+/*:2*//*3:*/
+
+int
+critbit0_contains(critbit0_tree*t,const char*u){
+const uint8*ubytes= (void*)u;
+const size_t ulen= strlen(u);
+uint8*p= t->root;
+
+/*4:*/
+
+if(!p)return 0;
+
+/*:4*/
+
+/*5:*/
+
+while(1&(intptr_t)p){
+critbit0_node*q= (void*)(p-1);
+/*6:*/
+
+uint8 c= 0;
+if(q->byte<ulen)c= ubytes[q->byte];
+const int direction= (1+(q->otherbits|c))>>8;
+
+/*:6*/
+
+p= q->child[direction];
+}
+
+/*:5*/
+
+/*7:*/
+
+return 0==strcmp(u,(const char*)p);
+
+/*:7*/
+
+}
+
+/*:3*//*8:*/
+
+int critbit0_insert(critbit0_tree*t,const char*u)
+{
+const uint8*const ubytes= (void*)u;
+const size_t ulen= strlen(u);
+uint8*p= t->root;
+
+/*9:*/
+
+if(!p){
+#if 0
+char*x;
+int a= posix_memalign((void**)&x,sizeof(void*),ulen+1);
+if(a)return 0;
+memcpy(x,u,ulen+1);
+t->root= x;
+#else
+t->root = (char *)u;
+#endif
+return 2;
+}
+
+/*:9*/
+
+/*5:*/
+
+while(1&(intptr_t)p){
+critbit0_node*q= (void*)(p-1);
+/*6:*/
+
+uint8 c= 0;
+if(q->byte<ulen)c= ubytes[q->byte];
+const int direction= (1+(q->otherbits|c))>>8;
+
+/*:6*/
+
+p= q->child[direction];
+}
+
+/*:5*/
+
+/*10:*/
+
+/*11:*/
+
+uint32 newbyte;
+uint32 newotherbits;
+
+for(newbyte= 0;newbyte<ulen;++newbyte){
+if(p[newbyte]!=ubytes[newbyte]){
+newotherbits= p[newbyte]^ubytes[newbyte];
+goto different_byte_found;
+}
+}
+
+if(p[newbyte]!=0){
+newotherbits= p[newbyte];
+goto different_byte_found;
+}
+return 1;
+
+different_byte_found:
+
+/*:11*/
+
+/*12:*/
+
+while(newotherbits&(newotherbits-1))newotherbits&= newotherbits-1;
+newotherbits^= 255;
+uint8 c= p[newbyte];
+int newdirection= (1+(newotherbits|c))>>8;
+
+/*:12*/
+
+
+/*:10*/
+
+/*13:*/
+
+/*14:*/
+
+critbit0_node*newnode;
+if(posix_memalign((void**)&newnode,sizeof(void*),sizeof(critbit0_node)))return 0;
+allocated++;
+char*x;
+#if 0
+if(posix_memalign((void**)&x,sizeof(void*),ulen+1)){
+free(newnode);
+return 0;
+}
+memcpy(x,ubytes,ulen+1);
+#else
+x = (char *)u;
+#endif
+newnode->byte= newbyte;
+newnode->otherbits= newotherbits;
+newnode->child[1-newdirection]= x;
+
+/*:14*/
+
+/*15:*/
+
+void**wherep= &t->root;
+for(;;){
+uint8*p= *wherep;
+if(!(1&(intptr_t)p))break;
+critbit0_node*q= (void*)(p-1);
+if(q->byte> newbyte)break;
+if(q->byte==newbyte&&q->otherbits> newotherbits)break;
+uint8 c= 0;
+if(q->byte<ulen)c= ubytes[q->byte];
+const int direction= (1+(q->otherbits|c))>>8;
+wherep= q->child+direction;
+}
+
+newnode->child[newdirection]= *wherep;
+*wherep= (void*)(1+(char*)newnode);
+
+/*:15*/
+
+
+/*:13*/
+
+
+return 2;
+}
+
+/*:8*//*16:*/
+
+int critbit0_delete(critbit0_tree*t,const char*u){
+const uint8*ubytes= (void*)u;
+const size_t ulen= strlen(u);
+uint8*p= t->root;
+void**wherep= &t->root;
+void**whereq= 0;
+critbit0_node*q= 0;
+int direction= 0;
+
+/*17:*/
+
+if(!p)return 0;
+
+/*:17*/
+
+/*18:*/
+
+while(1&(intptr_t)p){
+whereq= wherep;
+q= (void*)(p-1);
+uint8 c= 0;
+if(q->byte<ulen)c= ubytes[q->byte];
+direction= (1+(q->otherbits|c))>>8;
+wherep= q->child+direction;
+p= *wherep;
+}
+
+/*:18*/
+
+/*19:*/
+
+if(0!=strcmp(u,(const char*)p))return 0;
+#if 0
+free(p);
+#endif
+
+/*:19*/
+
+/*20:*/
+
+if(!whereq){
+t->root= 0;
+return 1;
+}
+
+*whereq= q->child[1-direction];
+free(q);
+allocated--;
+/*:20*/
+
+
+return 1;
+}
+
+/*:16*//*21:*/
+
+static void
+traverse(void*top){
+/*22:*/
+
+uint8*p= top;
+
+if(1&(intptr_t)p){
+critbit0_node*q= (void*)(p-1);
+traverse(q->child[0]);
+traverse(q->child[1]);
+free(q);
+allocated--;
+}else{
+#if 0
+free(p);
+#endif
+}
+
+/*:22*/
+
+}
+
+void critbit0_clear(critbit0_tree*t)
+{
+if(t->root)traverse(t->root);
+t->root= NULL;
+}
+
+/*:21*//*23:*/
+
+static int
+allprefixed_traverse(uint8*top,
+int(*handle)(const char*,void*),void*arg){
+/*26:*/
+
+if(1&(intptr_t)top){
+critbit0_node*q= (void*)(top-1);
+int direction;
+for(direction= 0;direction<2;++direction)
+switch(allprefixed_traverse(q->child[direction],handle,arg)){
+case 1:break;
+case 0:return 0;
+default:return-1;
+}
+return 1;
+}
+
+/*:26*/
+
+/*27:*/
+
+return handle((const char*)top,arg);/*:27*/
+
+}
+
+int
+critbit0_allprefixed(critbit0_tree*t,const char*prefix,
+int(*handle)(const char*,void*),void*arg){
+const uint8*ubytes= (void*)prefix;
+const size_t ulen= strlen(prefix);
+uint8*p= t->root;
+uint8*top= p;
+size_t i;
+
+if(!p)return 1;
+/*24:*/
+
+while(1&(intptr_t)p){
+critbit0_node*q= (void*)(p-1);
+uint8 c= 0;
+if(q->byte<ulen)c= ubytes[q->byte];
+const int direction= (1+(q->otherbits|c))>>8;
+p= q->child[direction];
+if(q->byte<ulen)top= p;
+}
+
+/*:24*/
+
+/*25:*/
+
+for(i= 0;i<ulen;++i){
+if(p[i]!=ubytes[i])return 1;
+}
+
+/*:25*/
+
+
+return allprefixed_traverse(top,handle,arg);
+}
+
+/*:23*/
+/* end critbit */
+
+/* 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;
+	critbit0_tree ct;
+	char **words, **misswords;
+
+	words = strsplit(NULL, grab_file(NULL,
+					 argv[1] ? argv[1] : "/usr/share/dict/words",
+					 NULL), "\n");
+	ct.root = NULL;
+	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++)
+		critbit0_insert(&ct, words[i]);
+	stop = time_now();
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Nodes allocated: %zu (%zu bytes)\n",
+	       allocated, allocated * sizeof(critbit0_node));
+
+	printf("#02: Initial lookup (match): ");
+	fflush(stdout);
+	start = time_now();
+	for (i = 0; i < num; i++)
+		if (!critbit0_contains(&ct, 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 (critbit0_contains(&ct, 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 (!critbit0_contains(&ct, words[j]))
+			abort();
+	stop = time_now();
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("#05: Initial delete all: ");
+	fflush(stdout);
+	start = time_now();
+	for (i = 0; i < num; i++)
+		if (!critbit0_delete(&ct, 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++)
+		critbit0_insert(&ct, words[i]);
+	stop = time_now();
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("#07: Deleting first half: ");
+	fflush(stdout);
+	start = time_now();
+	for (i = 0; i < num; i+=2)
+		if (!critbit0_delete(&ct, 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)
+		critbit0_insert(&ct, 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 (!critbit0_contains(&ct, words[i]))
+			abort();
+	for (i = 0; i < num; i+=2) {
+		if (!critbit0_contains(&ct, 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 (critbit0_contains(&ct, words[i]))
+			abort();
+	for (i = 1; i < num; i+=2) {
+		if (critbit0_contains(&ct, 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 (!critbit0_delete(&ct, misswords[j]))
+			abort();
+		if (critbit0_insert(&ct, words[j]) != 2)
+			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 (!critbit0_delete(&ct, words[j]))
+			abort();
+		if (critbit0_insert(&ct, misswords[j]) != 2)
+			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 (!critbit0_delete(&ct, misswords[j]))
+			abort();
+		if (critbit0_insert(&ct, words[j]) != 2)
+			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 (!critbit0_contains(&ct, 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 (critbit0_contains(&ct, 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 (!critbit0_contains(&ct, words[j]))
+			abort();
+	stop = time_now();
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	return 0;
+}
diff --git a/lib/ccan/strset/tools/speed.c b/lib/ccan/strset/tools/speed.c
new file mode 100644
index 0000000000..9edb0718bc
--- /dev/null
+++ b/lib/ccan/strset/tools/speed.c
@@ -0,0 +1,243 @@
+/* Simple speed tests using strset code.
+ *
+ * Results on my 32 bit Intel(R) Core(TM) i5 CPU M 560  @ 2.67GHz, gcc 4.5.2:
+ * Run 100 times: Min-Max(Avg)
+ #01: Initial insert:   212-219(214)
+ #02: Initial lookup (match):   161-169(162)
+ #03: Initial lookup (miss):   157-163(158)
+ #04: Initial lookup (random):   450-479(453)
+ #05: Initial delete all:   126-137(128)
+ #06: Initial re-inserting:   193-198(194)
+ #07: Deleting first half:   99-102(99)
+ #08: Adding (a different) half:   143-154(144)
+ #09: Lookup after half-change (match):   183-189(184)
+ #10: Lookup after half-change (miss):   198-212(199)
+ #11: Churn 1:   274-282(276)
+ #12: Churn 2:   279-296(282)
+ #13: Churn 3:   278-294(280)
+ #14: Post-Churn lookup (match):   170-180(171)
+ #15: Post-Churn lookup (miss):   175-186(176)
+ #16: Post-Churn lookup (random):   522-534(525)
+ */
+#include <ccan/str_talloc/str_talloc.h>
+#include <ccan/grab_file/grab_file.h>
+#include <ccan/talloc/talloc.h>
+#include <ccan/time/time.h>
+#include <ccan/strset/strset.c>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/time.h>
+
+/* 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 strset set;
+	char **words, **misswords;
+
+	words = strsplit(NULL, grab_file(NULL,
+					 argv[1] ? argv[1] : "/usr/share/dict/words",
+					 NULL), "\n");
+	strset_init(&set);
+	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++)
+		strset_set(&set, words[i]);
+	stop = time_now();
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+#if 0
+	printf("Nodes allocated: %zu (%zu bytes)\n",
+	       allocated, allocated * sizeof(critbit0_node));
+#endif
+
+	printf("#02: Initial lookup (match): ");
+	fflush(stdout);
+	start = time_now();
+	for (i = 0; i < num; i++)
+		if (!strset_test(&set, 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 (strset_test(&set, 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 (!strset_test(&set, words[j]))
+			abort();
+	stop = time_now();
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("#05: Initial delete all: ");
+	fflush(stdout);
+	start = time_now();
+	for (i = 0; i < num; i++)
+		if (!strset_clear(&set, 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++)
+		strset_set(&set, words[i]);
+	stop = time_now();
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("#07: Deleting first half: ");
+	fflush(stdout);
+	start = time_now();
+	for (i = 0; i < num; i+=2)
+		if (!strset_clear(&set, 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)
+		strset_set(&set, 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 (!strset_test(&set, words[i]))
+			abort();
+	for (i = 0; i < num; i+=2) {
+		if (!strset_test(&set, 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 (strset_test(&set, words[i]))
+			abort();
+	for (i = 1; i < num; i+=2) {
+		if (strset_test(&set, 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 (!strset_clear(&set, misswords[j]))
+			abort();
+		if (!strset_set(&set, 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 (!strset_clear(&set, words[j]))
+			abort();
+		if (!strset_set(&set, 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 (!strset_clear(&set, misswords[j]))
+			abort();
+		if (!strset_set(&set, 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 (!strset_test(&set, 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 (strset_test(&set, 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 (!strset_test(&set, words[j]))
+			abort();
+	stop = time_now();
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	return 0;
+}