#define WT_SEND_BUF_SIZE 1428
#endif
+/* Default configuration */
+
+/* WRITE_TSDB_DEFAULT_DNS_TTL is the time we keep the dns cached info
+ * (seconds)
+ */
+#define WRITE_TSDB_DEFAULT_DNS_TTL 600
+
+/* WRITE_TSDB_DEFAULT_DNS_RANDOM_TTL helps define the max random
+ * time we keep the dns cached info :
+ * min = 0
+ * max = WRITE_TSDB_DEFAULT_DNS_RANDOM_TTL * get_plugin_interval()
+ */
+#define WRITE_TSDB_DEFAULT_DNS_RANDOM_TTL 15
+
/*
* Private variables
*/
struct wt_callback {
- struct addrinfo *sock_info;
- cdtime_t sock_info_last_update;
+ struct addrinfo *ai;
+ cdtime_t ai_last_update;
int sock_fd;
char *node;
cdtime_t send_buf_init_time;
pthread_mutex_t send_lock;
+
+ _Bool connect_failed_log_enabled;
+ int connect_dns_failed_attempts_remaining;
+ cdtime_t next_random_ttl;
};
-static cdtime_t dnsttl = TIME_T_TO_CDTIME_T_STATIC(60);
+static cdtime_t dnsttl = TIME_T_TO_CDTIME_T_STATIC(WRITE_TSDB_DEFAULT_DNS_TTL);
+static cdtime_t dnsrandomttl = 0;
/*
* Functions
return status;
}
+static cdtime_t new_random_ttl() {
+ if (dnsrandomttl == 0)
+ return 0;
+
+ time_t ttl = (time_t)(CDTIME_T_TO_DOUBLE(dnsrandomttl) * ((double)random()) /
+ (((double)RAND_MAX) + 1.0));
+ return TIME_T_TO_CDTIME_T(ttl);
+}
+
static int wt_callback_init(struct wt_callback *cb) {
int status;
cdtime_t now;
return 0;
now = cdtime();
- if ((cb->sock_info_last_update + dnsttl) < now) {
- if (cb->sock_info) {
- freeaddrinfo(cb->sock_info);
- cb->sock_info = NULL;
+ if (cb->ai) {
+ /* When we are here, we still have the IP in cache.
+ * If we have remaining attempts without calling the DNS, we update the
+ * last_update date so we keep the info until next time.
+ * If there is no more attempts, we need to flush the cache.
+ */
+
+ if ((cb->ai_last_update + dnsttl + cb->next_random_ttl) < now) {
+ cb->next_random_ttl = new_random_ttl();
+ if (cb->connect_dns_failed_attempts_remaining > 0) {
+ /* Warning : this is run under send_lock mutex.
+ * This is why we do not use another mutex here.
+ * */
+ cb->ai_last_update = now;
+ cb->connect_dns_failed_attempts_remaining--;
+ } else {
+ freeaddrinfo(cb->ai);
+ cb->ai = NULL;
+ }
}
}
- if (NULL == cb->sock_info) {
+ if (cb->ai == NULL) {
+ if ((cb->ai_last_update + dnsttl + cb->next_random_ttl) >= now) {
+ DEBUG("write_tsdb plugin: too many getaddrinfo(%s, %s) failures", node,
+ service);
+ return (-1);
+ }
+ cb->ai_last_update = now;
+ cb->next_random_ttl = new_random_ttl();
+
struct addrinfo ai_hints = {
.ai_family = AF_UNSPEC,
.ai_flags = AI_ADDRCONFIG,
.ai_socktype = SOCK_STREAM,
};
- if ((cb->sock_info_last_update + dnsttl) >= now) {
- DEBUG("write_tsdb plugin: too many getaddrinfo (%s, %s) failures", node,
- service);
- return (-1);
- }
-
- cb->sock_info_last_update = now;
- status = getaddrinfo(node, service, &ai_hints, &(cb->sock_info));
+ status = getaddrinfo(node, service, &ai_hints, &cb->ai);
if (status != 0) {
- if (cb->sock_info) {
- freeaddrinfo(cb->sock_info);
- cb->sock_info = NULL;
+ if (cb->ai) {
+ freeaddrinfo(cb->ai);
+ cb->ai = NULL;
}
if (cb->connect_failed_log_enabled) {
- ERROR("write_tsdb plugin: getaddrinfo (%s, %s) failed: %s", node,
+ ERROR("write_tsdb plugin: getaddrinfo(%s, %s) failed: %s", node,
service, gai_strerror(status));
cb->connect_failed_log_enabled = 0;
}
}
}
- assert(cb->sock_info != NULL);
- for (struct addrinfo *ai_ptr = cb->sock_info; ai_ptr != NULL;
- ai_ptr = ai_ptr->ai_next) {
- cb->sock_fd =
- socket(ai_ptr->ai_family, ai_ptr->ai_socktype, ai_ptr->ai_protocol);
+ assert(cb->ai != NULL);
+ for (struct addrinfo *ai = cb->ai; ai != NULL; ai = ai->ai_next) {
+ cb->sock_fd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
if (cb->sock_fd < 0)
continue;
set_sock_opts(cb->sock_fd);
- status = connect(cb->sock_fd, ai_ptr->ai_addr, ai_ptr->ai_addrlen);
+ status = connect(cb->sock_fd, ai->ai_addr, ai->ai_addrlen);
if (status != 0) {
close(cb->sock_fd);
cb->sock_fd = -1;
return -1;
}
+ if (0 == cb->connect_failed_log_enabled) {
+ WARNING("write_tsdb plugin: Connecting to %s:%s succeeded.", node, service);
+ cb->connect_failed_log_enabled = 1;
+ }
+ cb->connect_dns_failed_attempts_remaining = 1;
+
wt_reset_buffer(cb);
return 0;
return -1;
}
cb->sock_fd = -1;
+ cb->connect_failed_log_enabled = 1;
+ cb->next_random_ttl = new_random_ttl();
pthread_mutex_init(&cb->send_lock, NULL);
}
static int wt_config(oconfig_item_t *ci) {
+ _Bool config_random_ttl = 0;
+
for (int i = 0; i < ci->children_num; i++) {
oconfig_item_t *child = ci->children + i;
if (strcasecmp("Node", child->key) == 0)
wt_config_tsd(child);
- if (strcasecmp("DNS_Cache_TTL", child->key) == 0) {
- int ttl;
- cf_util_get_int(child, &ttl);
- dnsttl = TIME_T_TO_CDTIME_T(ttl);
+ else if (strcasecmp("ResolveInterval", child->key) == 0)
+ cf_util_get_cdtime(child, &dnsttl);
+ else if (strcasecmp("ResolveJitter", child->key) == 0) {
+ config_random_ttl = 1;
+ cf_util_get_cdtime(child, &dnsrandomttl);
} else {
ERROR("write_tsdb plugin: Invalid configuration "
"option: %s.",
}
}
+ if (!config_random_ttl)
+ dnsrandomttl = CDTIME_T_TO_DOUBLE(WRITE_TSDB_DEFAULT_DNS_RANDOM_TTL *
+ plugin_get_interval());
+
return 0;
}
projects / collectd.git / blobdiff