MEDIUM: resolvers: add a ref on server to the used A/AAAA answer item
This patch adds a head list into answer items on servers which use
this record to set their IPs. It makes lookup on duplicated ip faster and
allow to check immediatly if an item is still valid renewing the IP.
This results in better performances on A/AAAA resolutions.
This is an optimization but it could avoid to trigger the haproxy's
internal wathdog in some circumstances. And for this reason
it should be backported as far we can (2.0 ?)
diff --git a/src/resolvers.c b/src/resolvers.c
index 85b10d6..8864240 100644
--- a/src/resolvers.c
+++ b/src/resolvers.c
@@ -575,7 +575,7 @@
struct resolvers *resolvers = res->resolvers;
struct resolv_requester *req;
struct resolv_answer_item *item, *itemback;
- struct server *srv;
+ struct server *srv, *srvback;
struct resolv_srvrq *srvrq;
list_for_each_entry_safe(item, itemback, &res->response.answer_list, list) {
@@ -592,32 +592,36 @@
/* Remove obsolete items */
if (tick_is_lt(tick_add(item->last_seen, resolvers->hold.obsolete), now_ms)) {
- if (item->type != DNS_RTYPE_SRV)
- goto rm_obselete_item;
-
- list_for_each_entry(req, &res->requesters, list) {
- if ((srvrq = objt_resolv_srvrq(req->owner)) == NULL)
- continue;
-
+ if (item->type == DNS_RTYPE_A || item->type == DNS_RTYPE_AAAA) {
/* Remove any associated server */
- for (srv = srvrq->proxy->srv; srv != NULL; srv = srv->next) {
- HA_SPIN_LOCK(SERVER_LOCK, &srv->lock);
- if (srv->srvrq == srvrq && srv->svc_port == item->port &&
- item->data_len == srv->hostname_dn_len &&
- !resolv_hostname_cmp(srv->hostname_dn, item->target, item->data_len)) {
- resolv_unlink_resolution(srv->resolv_requester, 0);
- srvrq_update_srv_status(srv, 1);
- ha_free(&srv->hostname);
- ha_free(&srv->hostname_dn);
- srv->hostname_dn_len = 0;
- memset(&srv->addr, 0, sizeof(srv->addr));
- srv->svc_port = 0;
+ list_for_each_entry_safe(srv, srvback, &item->attached_servers, ip_rec_item) {
+ LIST_DEL_INIT(&srv->ip_rec_item);
+ }
+ }
+ else if (item->type == DNS_RTYPE_SRV) {
+ list_for_each_entry(req, &res->requesters, list) {
+ if ((srvrq = objt_resolv_srvrq(req->owner)) == NULL)
+ continue;
+
+ /* Remove any associated server */
+ for (srv = srvrq->proxy->srv; srv != NULL; srv = srv->next) {
+ HA_SPIN_LOCK(SERVER_LOCK, &srv->lock);
+ if (srv->srvrq == srvrq && srv->svc_port == item->port &&
+ item->data_len == srv->hostname_dn_len &&
+ !resolv_hostname_cmp(srv->hostname_dn, item->target, item->data_len)) {
+ resolv_unlink_resolution(srv->resolv_requester, 0);
+ srvrq_update_srv_status(srv, 1);
+ ha_free(&srv->hostname);
+ ha_free(&srv->hostname_dn);
+ srv->hostname_dn_len = 0;
+ memset(&srv->addr, 0, sizeof(srv->addr));
+ srv->svc_port = 0;
+ }
+ HA_SPIN_UNLOCK(SERVER_LOCK, &srv->lock);
}
- HA_SPIN_UNLOCK(SERVER_LOCK, &srv->lock);
}
}
- rm_obselete_item:
LIST_DELETE(&item->list);
if (item->ar_item) {
pool_free(resolv_answer_item_pool, item->ar_item);
@@ -902,6 +906,7 @@
/* initialization */
answer_record->ar_item = NULL;
answer_record->last_seen = TICK_ETERNITY;
+ LIST_INIT(&answer_record->attached_servers);
offset = 0;
len = resolv_read_name(resp, bufend, reader, tmpname, DNS_MAX_NAME_SIZE, &offset, 0);
@@ -1153,6 +1158,7 @@
if (answer_record == NULL)
goto invalid_resp;
answer_record->last_seen = TICK_ETERNITY;
+ LIST_INIT(&answer_record->attached_servers);
offset = 0;
len = resolv_read_name(resp, bufend, reader, tmpname, DNS_MAX_NAME_SIZE, &offset, 0);
@@ -1311,7 +1317,6 @@
/* Save the number of records we really own */
r_res->header.arcount = nb_saved_records;
-
resolv_check_response(resolution);
return RSLV_RESP_VALID;
@@ -1335,9 +1340,9 @@
struct resolv_options *resolv_opts, void *currentip,
short currentip_sin_family,
void **newip, short *newip_sin_family,
- void *owner)
+ struct server *owner)
{
- struct resolv_answer_item *record;
+ struct resolv_answer_item *record, *found_record = NULL;
int family_priority;
int currentip_found;
unsigned char *newip4, *newip6;
@@ -1346,6 +1351,10 @@
int score, max_score;
int allowed_duplicated_ip;
+ /* srv is linked to an alive ip record */
+ if (owner && LIST_INLIST(&owner->ip_rec_item))
+ return RSLV_UPD_NO;
+
family_priority = resolv_opts->family_prio;
allowed_duplicated_ip = resolv_opts->accept_duplicate_ip;
*newip = newip4 = newip6 = NULL;
@@ -1410,9 +1419,25 @@
/* Check if the IP found in the record is already affected to a
* member of a group. If not, the score should be incremented
* by 2. */
- if (owner && snr_check_ip_callback(owner, ip, &ip_type)) {
- if (!allowed_duplicated_ip) {
- continue;
+ if (owner) {
+ struct server *srv;
+ int already_used = 0;
+
+ list_for_each_entry(srv, &record->attached_servers, ip_rec_item) {
+ if (srv == owner)
+ continue;
+ if (srv->proxy == owner->proxy) {
+ already_used = 1;
+ break;
+ }
+ }
+ if (already_used) {
+ if (!allowed_duplicated_ip) {
+ continue;
+ }
+ }
+ else {
+ score += 2;
}
} else {
score += 2;
@@ -1439,9 +1464,15 @@
newip4 = ip;
else
newip6 = ip;
+ found_record = record;
currentip_found = currentip_sel;
- if (score == 15)
+ if (score == 15) {
+ /* this was not registered on the current record but it matches
+ * let's fix it (it may comes from state file */
+ if (owner)
+ LIST_APPEND(&found_record->attached_servers, &owner->ip_rec_item);
return RSLV_UPD_NO;
+ }
max_score = score;
}
} /* list for each record entries */
@@ -1494,6 +1525,12 @@
return RSLV_UPD_NO;
not_found:
+
+ /* the ip of this record was chosen for the server */
+ if (owner && found_record) {
+ LIST_APPEND(&found_record->attached_servers, &owner->ip_rec_item);
+ }
+
list_for_each_entry(record, &r_res->answer_list, list) {
/* Move the first record to the end of the list, for internal
* round robin */
@@ -1832,12 +1869,18 @@
{
struct resolv_resolution *res;
struct resolv_requester *req;
+ struct server *srv;
/* Nothing to do */
if (!requester || !requester->resolution)
return;
res = requester->resolution;
+ /* remove ref from the resolution answer item list to the requester */
+ if ((srv = objt_server(requester->owner)) != NULL) {
+ LIST_DEL_INIT(&srv->ip_rec_item);
+ }
+
/* Clean up the requester */
LIST_DELETE(&requester->list);
requester->resolution = NULL;
diff --git a/src/server.c b/src/server.c
index c2c52e7..4a7044b 100644
--- a/src/server.c
+++ b/src/server.c
@@ -2160,6 +2160,7 @@
srv->proxy = proxy;
srv->pendconns = EB_ROOT;
LIST_APPEND(&servers_list, &srv->global_list);
+ LIST_INIT(&srv->ip_rec_item);
srv->next_state = SRV_ST_RUNNING; /* early server setup */
srv->last_change = now.tv_sec;
@@ -3525,6 +3526,7 @@
if (!snr_update_srv_status(s, 1)) {
memset(&s->addr, 0, sizeof(s->addr));
HA_SPIN_UNLOCK(SERVER_LOCK, &s->lock);
+ LIST_DEL_INIT(&s->ip_rec_item);
return 0;
}
HA_SPIN_UNLOCK(SERVER_LOCK, &s->lock);