djbdns/sme9/110-dnscache-cachestats.patch

#
# This patch to djbdns 1.05 modifies the dnscache program to keep a
# counter of cache hits and cache misses.
#
# Two new fields are added to the ``stats'' output line:
#  . the fifth number is the number of cache hits
#  . the sixth number is the number of cache misses
# e.g.
#  @400000003fa92ccc317d70f4 stats 3 1201 1 0 21 49
# indicates 21 hits and 49 misses.
#
# James Raftery <james@now.ie>  6 Nov. 2003
#
--- a/cache.c
+++ b/cache.c
@@ -7,6 +7,11 @@
 
 uint64 cache_motion = 0;
 
+/* record cache stats */
+/* James Raftery <james@now.ie> 6 Nov. 2003 */
+uint64 cache_hit = 0;
+uint64 cache_miss = 0;
+
 static char *x = 0;
 static uint32 size;
 static uint32 hsize;
@@ -112,15 +117,20 @@ char *cache_get(const char *key,unsigned
         if (u > size - pos - 20 - keylen) cache_impossible();
         *datalen = u;
 
+        cache_hit++;
         return x + pos + 20 + keylen;
       }
     }
     nextpos = prevpos ^ get4(pos);
     prevpos = pos;
     pos = nextpos;
-    if (++loop > 100) return 0; /* to protect against hash flooding */
+    if (++loop > 100) { /* to protect against hash flooding */
+      cache_miss++;
+      return 0;
+    }
   }
 
+  cache_miss++;
   return 0;
 }
 
--- a/cache.h
+++ b/cache.h
@@ -5,6 +5,12 @@
 #include "uint64.h"
 
 extern uint64 cache_motion;
+
+/* record cache stats */
+/* James Raftery <james@now.ie> 6 Nov. 2003 */
+extern uint64 cache_hit;
+extern uint64 cache_miss;
+
 extern int cache_init(unsigned int);
 extern void cache_set(const char *,unsigned int,const char *,unsigned int,uint32);
 extern char *cache_get(const char *,unsigned int,unsigned int *,uint32 *);
--- a/log.c
+++ b/log.c
@@ -279,6 +279,12 @@ void log_stats(void)
   time_t cur = time(NULL);
   extern uint64 numqueries;
   extern uint64 cache_motion;
+
+  /* record cache stats */
+  /* James Raftery <james@now.ie> 6 Nov. 2003 */
+  extern uint64 cache_hit;
+  extern uint64 cache_miss;
+
   extern int uactive;
   extern int tactive;
 
@@ -290,6 +296,8 @@ void log_stats(void)
   number(numqueries); space();
   number(cache_motion); space();
   number(uactive); space();
-  number(tactive);
+  number(tactive); space();
+  number(cache_hit); space();
+  number(cache_miss);
   line();
 }
1	#
2	# This patch to djbdns 1.05 modifies the dnscache program to keep a
3	# counter of cache hits and cache misses.
4	#
5	# Two new fields are added to the ``stats'' output line:
6	# . the fifth number is the number of cache hits
7	# . the sixth number is the number of cache misses
8	# e.g.
9	# @400000003fa92ccc317d70f4 stats 3 1201 1 0 21 49
10	# indicates 21 hits and 49 misses.
11	#
12	# James Raftery <james@now.ie> 6 Nov. 2003
13	#
14	--- a/cache.c
15	+++ b/cache.c
16	@@ -7,6 +7,11 @@
17
18	uint64 cache_motion = 0;
19
20	+/* record cache stats */
21	+/* James Raftery <james@now.ie> 6 Nov. 2003 */
22	+uint64 cache_hit = 0;
23	+uint64 cache_miss = 0;
24	+
25	static char *x = 0;
26	static uint32 size;
27	static uint32 hsize;
28	@@ -112,15 +117,20 @@ char cache_get(const char key,unsigned
29	if (u > size - pos - 20 - keylen) cache_impossible();
30	*datalen = u;
31
32	+ cache_hit++;
33	return x + pos + 20 + keylen;
34	}
35	}
36	nextpos = prevpos ^ get4(pos);
37	prevpos = pos;
38	pos = nextpos;
39	- if (++loop > 100) return 0; /* to protect against hash flooding */
40	+ if (++loop > 100) { /* to protect against hash flooding */
41	+ cache_miss++;
42	+ return 0;
43	+ }
44	}
45
46	+ cache_miss++;
47	return 0;
48	}
49
50	--- a/cache.h
51	+++ b/cache.h
52	@@ -5,6 +5,12 @@
53	#include "uint64.h"
54
55	extern uint64 cache_motion;
56	+
57	+/* record cache stats */
58	+/* James Raftery <james@now.ie> 6 Nov. 2003 */
59	+extern uint64 cache_hit;
60	+extern uint64 cache_miss;
61	+
62	extern int cache_init(unsigned int);
63	extern void cache_set(const char ,unsigned int,const char ,unsigned int,uint32);
64	extern char cache_get(const char ,unsigned int,unsigned int ,uint32 );
65	--- a/log.c
66	+++ b/log.c
67	@@ -279,6 +279,12 @@ void log_stats(void)
68	time_t cur = time(NULL);
69	extern uint64 numqueries;
70	extern uint64 cache_motion;
71	+
72	+ /* record cache stats */
73	+ /* James Raftery <james@now.ie> 6 Nov. 2003 */
74	+ extern uint64 cache_hit;
75	+ extern uint64 cache_miss;
76	+
77	extern int uactive;
78	extern int tactive;
79
80	@@ -290,6 +296,8 @@ void log_stats(void)
81	number(numqueries); space();
82	number(cache_motion); space();
83	number(uactive); space();
84	- number(tactive);
85	+ number(tactive); space();
86	+ number(cache_hit); space();
87	+ number(cache_miss);
88	line();
89	}