config file settings for message cache.

git-svn-id: file:///svn/unbound/trunk@196 be551aaa-1e26-0410-a405-d3ace91eadb9

daemon/daemon.c

@@ -48,6 +48,7 @@
 #include "util/log.h"
 #include "util/config_file.h"
 #include "util/data/msgreply.h"
+#include "util/storage/slabhash.h"
 #include "services/listen_dnsport.h"
 #include <signal.h>
 
@@ -117,7 +118,7 @@ daemon_init()
 	signal_handling_record();
 	checklock_start();
 	daemon->need_to_exit = 0;
-	daemon->msg_cache = lruhash_create(HASH_DEFAULT_STARTARRAY,
+	daemon->msg_cache = slabhash_create(4, HASH_DEFAULT_STARTARRAY,
 		HASH_DEFAULT_MAXMEM, msgreply_sizefunc, query_info_compare,
 		query_entry_delete, reply_info_delete, NULL);
 	if(!daemon->msg_cache) {
@@ -311,7 +312,7 @@ daemon_delete(struct daemon* daemon)
 	if(!daemon)
 		return;
 	listening_ports_free(daemon->ports);
-	lruhash_delete(daemon->msg_cache);
+	slabhash_delete(daemon->msg_cache);
 	alloc_clear(&daemon->superalloc);
 	free(daemon->cwd);
 	free(daemon->pidfile);

daemon/daemon.h

@@ -47,7 +47,7 @@
 struct config_file;
 struct worker;
 struct listen_port;
-struct lruhash;
+struct slabhash;
 
 /**
  * Structure holding worker list.
@@ -73,7 +73,7 @@ struct daemon {
 	/** master allocation cache */
 	struct alloc_cache superalloc;
 	/** the message cache, content is struct msgreply_entry* */
-	struct lruhash* msg_cache;
+	struct slabhash* msg_cache;
 };
 
 /**

daemon/unbound.c

@@ -44,6 +44,8 @@
 #include "util/log.h"
 #include "daemon/daemon.h"
 #include "util/config_file.h"
+#include "util/storage/slabhash.h"
+#include "util/data/msgreply.h"
 #include <signal.h>
 #include <fcntl.h>
 #include <pwd.h>
@@ -80,6 +82,17 @@ apply_dir(struct daemon* daemon, struct config_file* cfg, int cmdline_verbose)
 				fatal_exit("malloc failed");
 		}
 	}
+	if(cfg->msg_cache_size != slabhash_get_size(daemon->msg_cache) ||
+		cfg->msg_cache_slabs != daemon->msg_cache->size) {
+		slabhash_delete(daemon->msg_cache);
+		daemon->msg_cache = slabhash_create(cfg->msg_cache_slabs, 
+			HASH_DEFAULT_STARTARRAY, cfg->msg_cache_size, 
+			msgreply_sizefunc, query_info_compare,
+			query_entry_delete, reply_info_delete, NULL);
+		if(!daemon->msg_cache) {
+			fatal_exit("malloc failure updating config settings");
+		}
+	}
 }
 
 /** Read existing pid from pidfile. */

daemon/worker.c

@@ -47,6 +47,7 @@
 #include "daemon/daemon.h"
 #include "util/netevent.h"
 #include "util/config_file.h"
+#include "util/storage/slabhash.h"
 #include "services/listen_dnsport.h"
 #include "services/outside_network.h"
 
@@ -159,7 +160,7 @@ worker_handle_reply(struct comm_point* c, void* arg, int error,
 		log_err("out of memory");
 		return 0;
 	}
-	lruhash_insert(worker->daemon->msg_cache, worker->query_hash, 
+	slabhash_insert(worker->daemon->msg_cache, worker->query_hash, 
 		&e->entry, rep);
 	return 0;
 }
@@ -290,7 +291,7 @@ worker_handle_request(struct comm_point* c, void* arg, int error,
 		return 1;
 	}
 	h = query_info_hash(&worker->qinfo);
-	if((e=lruhash_lookup(worker->daemon->msg_cache, h, &worker->qinfo, 
+	if((e=slabhash_lookup(worker->daemon->msg_cache, h, &worker->qinfo, 
 		0))) {
 		/* answer from cache */
 		log_info("answer from the cache");

doc/Changelog

@@ -1,3 +1,6 @@
+26 March 2007: Wouter
+	- config settings for slab hash message cache.
+
 23 March 2007: Wouter
 	- review of yesterday's commits.
 	- covered up memory leak of the entry locks.

doc/example.conf

@@ -36,6 +36,14 @@ server:
 	# But also takes more system resources (for open sockets).
 	# outgoing-range: 16
 
+	# the amount of memory to use for the message cache.
+	# in bytes. default is 4 Mb
+	# msg-cache-size: 4194304
+
+	# the number of slabs to use for the message cache.
+	# more slabs reduce lock contention, but fracture memory usage.
+	# msg-cache-slabs: 4
+
 	# Enable IPv4, "yes" or "no".
 	# do-ip4: yes
 

doc/unbound.conf.5

@@ -63,6 +63,12 @@ Number of ports to open. This number is opened per thread for every outgoing
 query interface. Must be at least 1. Default is 16.
 Larger numbers give more protection against spoofing attempts, but need
 extra resources from the operating system.
+.It \fBmsg-cache-size:\fR <number>
+Number of bytes size of the message cache. Default is 4 megabytes.
+.It \fBmsg-cache-slabs:\fR <number>
+Number of slabs in the message cache. Slabs reduce lock contention by threads.
+Must be set to a power of 2. Setting (close) to the number of cpus is a 
+reasonable guess.
 .It \fBdo-ip4:\fR <yes or no>
 Enable or disable whether ip4 queries are answered. Default is yes.
 .It \fBdo-ip6:\fR <yes or no>

testcode/unitmain.c

@@ -97,6 +97,26 @@ net_test()
 	unit_assert( !str_is_ip6("213.154.224.12") );
 	unit_assert( !str_is_ip6("213.154.224.255") );
 	unit_assert( !str_is_ip6("255.255.255.0") );
+	unit_assert( is_pow2(0) );
+	unit_assert( is_pow2(1) );
+	unit_assert( is_pow2(2) );
+	unit_assert( is_pow2(4) );
+	unit_assert( is_pow2(8) );
+	unit_assert( is_pow2(16) );
+	unit_assert( is_pow2(1024) );
+	unit_assert( is_pow2(1024*1024) );
+	unit_assert( is_pow2(1024*1024*1024) );
+	unit_assert( !is_pow2(3) );
+	unit_assert( !is_pow2(5) );
+	unit_assert( !is_pow2(6) );
+	unit_assert( !is_pow2(7) );
+	unit_assert( !is_pow2(9) );
+	unit_assert( !is_pow2(10) );
+	unit_assert( !is_pow2(11) );
+	unit_assert( !is_pow2(17) );
+	unit_assert( !is_pow2(23) );
+	unit_assert( !is_pow2(257) );
+	unit_assert( !is_pow2(259) );
 }
 
 /** put dname into buffer */

util/config_file.c

@@ -77,6 +77,8 @@ config_create()
 	cfg->do_tcp = 1;
 	cfg->outgoing_base_port = cfg->port + 1000;
 	cfg->outgoing_num_ports = 16;
+	cfg->msg_cache_size = 4 * 1024 * 1024;
+	cfg->msg_cache_slabs = 4;
 	if(!(cfg->fwd_address = strdup(""))) {config_delete(cfg); return NULL;}
 	if(!(cfg->username = strdup(""))) {config_delete(cfg); return NULL;}
 	if(!(cfg->chrootdir = strdup(""))) {config_delete(cfg); return NULL;}

util/config_file.h

@@ -69,6 +69,11 @@ struct config_file {
 	/** outgoing port range number of ports (per thread, per if) */
 	int outgoing_num_ports;
 
+	/** size of the message cache */
+	size_t msg_cache_size;
+	/** slabs in the message cache. */
+	size_t msg_cache_slabs;
+
 	/** forwarder address. string. If not NULL fwder mode is enabled. */
 	char* fwd_address;
 	/** forwarder port */

util/configlexer.lex

@@ -114,6 +114,8 @@ username{COLON}		{ LEXOUT(("v(%s) ", yytext)); return VAR_USERNAME;}
 directory{COLON}	{ LEXOUT(("v(%s) ", yytext)); return VAR_DIRECTORY;}
 logfile{COLON}		{ LEXOUT(("v(%s) ", yytext)); return VAR_LOGFILE;}
 pidfile{COLON}		{ LEXOUT(("v(%s) ", yytext)); return VAR_PIDFILE;}
+msg-cache-size{COLON}	{ LEXOUT(("v(%s) ", yytext)); return VAR_MSG_CACHE_SIZE;}
+msg-cache-slabs{COLON}	{ LEXOUT(("v(%s) ", yytext)); return VAR_MSG_CACHE_SLABS;}
 {NEWLINE}		{ LEXOUT(("NL\n")); cfg_parser->line++;}
 
 	/* Quoted strings. Strip leading and ending quotes */

util/configparser.y

@@ -46,6 +46,7 @@
 
 #include "util/configyyrename.h"
 #include "util/config_file.h"
+#include "util/net_help.h"
 
 int ub_c_lex(void);
 void ub_c_error(const char *message);
@@ -71,6 +72,7 @@ extern struct config_parser_state* cfg_parser;
 %token VAR_DO_IP4 VAR_DO_IP6 VAR_DO_UDP VAR_DO_TCP
 %token VAR_FORWARD_TO VAR_FORWARD_TO_PORT VAR_CHROOT
 %token VAR_USERNAME VAR_DIRECTORY VAR_LOGFILE VAR_PIDFILE
+%token VAR_MSG_CACHE_SIZE VAR_MSG_CACHE_SLABS
 
 %%
 toplevelvars: /* empty */ | toplevelvars toplevelvar ;
@@ -90,7 +92,8 @@ content_server: server_num_threads | server_verbosity | server_port |
 	server_outgoing_port | server_outgoing_range | server_do_ip4 |
 	server_do_ip6 | server_do_udp | server_do_tcp | server_forward_to |
 	server_forward_to_port | server_interface | server_chroot | 
-	server_username | server_directory | server_logfile | server_pidfile;
+	server_username | server_directory | server_logfile | server_pidfile |
+	server_msg_cache_size | server_msg_cache_slabs;
 server_num_threads: VAR_NUM_THREADS STRING 
 	{ 
 		OUTYY(("P(server_num_threads:%s)\n", $2)); 
@@ -236,6 +239,28 @@ server_pidfile: VAR_PIDFILE STRING
 		cfg_parser->cfg->pidfile = $2;
 	}
 	;
+server_msg_cache_size: VAR_MSG_CACHE_SIZE STRING
+	{
+		OUTYY(("P(server_msg_cache_size:%s)\n", $2));
+		if(atoi($2) == 0)
+			yyerror("number expected");
+		else cfg_parser->cfg->msg_cache_size = atoi($2);
+		free($2);
+	}
+	;
+server_msg_cache_slabs: VAR_MSG_CACHE_SLABS STRING
+	{
+		OUTYY(("P(server_msg_cache_slabs:%s)\n", $2));
+		if(atoi($2) == 0)
+			yyerror("number expected");
+		else {
+			cfg_parser->cfg->msg_cache_slabs = atoi($2);
+			if(!is_pow2(cfg_parser->cfg->msg_cache_slabs))
+				yyerror("must be a power of 2");
+		}
+		free($2);
+	}
+	;
 %%
 
 /* parse helper routines could be here */

util/net_help.c

@@ -87,3 +87,10 @@ fd_set_nonblock(int s)
 	}
 	return 1;
 }
+
+int 
+is_pow2(size_t num)
+{
+	if(num == 0) return 1;
+	return (num & (num-1)) == 0;
+}

util/net_help.h

@@ -66,4 +66,11 @@ write_socket(int s, const void *buf, size_t size);
  */
 int fd_set_nonblock(int s); 
 
+/**
+ * See if number is a power of 2.
+ * @param num: the value.
+ * @return: true if the number is a power of 2.
+ */
+int is_pow2(size_t num);
+
 #endif /* NET_HELP_H */

util/storage/slabhash.c

@@ -131,3 +131,14 @@ void slabhash_status(struct slabhash* sl, const char* id, int extended)
 		lruhash_status(sl->array[i], num, extended);
 	}
 }
+
+size_t slabhash_get_size(struct slabhash* sl)
+{
+	size_t i, total = 0;
+	for(i=0; i<sl->size; i++) {
+		lock_quick_lock(&sl->array[i]->lock);
+		total += sl->array[i]->space_max;
+		lock_quick_unlock(&sl->array[i]->lock);
+	}
+	return total;
+}

util/storage/slabhash.h

@@ -134,4 +134,10 @@ void slabhash_remove(struct slabhash* table, hashvalue_t hash, void* key);
  */
 void slabhash_status(struct slabhash* table, const char* id, int extended);
 
+/**
+ * Retrieve slab hash total size.
+ * @param table: hash table.
+ */
+size_t slabhash_get_size(struct slabhash* table);
+
 #endif /* UTIL_STORAGE_SLABHASH_H */