diff --git a/iterator/iter_delegpt.c b/iterator/iter_delegpt.c index 4bffa1b3..fd07aaa1 100644 --- a/iterator/iter_delegpt.c +++ b/iterator/iter_delegpt.c @@ -78,6 +78,7 @@ struct delegpt* delegpt_copy(struct delegpt* dp, struct regional* region) if(!delegpt_add_ns(copy, region, ns->name, ns->lame, ns->tls_auth_name, ns->port)) return NULL; + copy->nslist->cache_lookup_count = ns->cache_lookup_count; copy->nslist->resolved = ns->resolved; copy->nslist->got4 = ns->got4; copy->nslist->got6 = ns->got6; @@ -121,6 +122,7 @@ delegpt_add_ns(struct delegpt* dp, struct regional* region, uint8_t* name, ns->namelen = len; dp->nslist = ns; ns->name = regional_alloc_init(region, name, ns->namelen); + ns->cache_lookup_count = 0; ns->resolved = 0; ns->got4 = 0; ns->got6 = 0; @@ -620,6 +622,7 @@ int delegpt_add_ns_mlc(struct delegpt* dp, uint8_t* name, uint8_t lame, } ns->next = dp->nslist; dp->nslist = ns; + ns->cache_lookup_count = 0; ns->resolved = 0; ns->got4 = 0; ns->got6 = 0; diff --git a/iterator/iter_delegpt.h b/iterator/iter_delegpt.h index 62c8edc5..586597a6 100644 --- a/iterator/iter_delegpt.h +++ b/iterator/iter_delegpt.h @@ -101,6 +101,8 @@ struct delegpt_ns { uint8_t* name; /** length of name */ size_t namelen; + /** number of cache lookups for the name */ + int cache_lookup_count; /** * If the name has been resolved. false if not queried for yet. * true if the A, AAAA queries have been generated. diff --git a/iterator/iter_utils.c b/iterator/iter_utils.c index 3e13e595..56b184a0 100644 --- a/iterator/iter_utils.c +++ b/iterator/iter_utils.c @@ -1209,6 +1209,9 @@ int iter_lookup_parent_glue_from_cache(struct module_env* env, struct delegpt_ns* ns; size_t num = delegpt_count_targets(dp); for(ns = dp->nslist; ns; ns = ns->next) { + if(ns->cache_lookup_count > ITERATOR_NAME_CACHELOOKUP_MAX_PSIDE) + continue; + ns->cache_lookup_count++; /* get cached parentside A */ akey = rrset_cache_lookup(env->rrset_cache, ns->name, ns->namelen, LDNS_RR_TYPE_A, qinfo->qclass, diff --git a/iterator/iter_utils.h b/iterator/iter_utils.h index 8583fde5..850be96a 100644 --- a/iterator/iter_utils.h +++ b/iterator/iter_utils.h @@ -62,6 +62,15 @@ struct ub_packed_rrset_key; struct module_stack; struct outside_network; +/* max number of lookups in the cache for target nameserver names. + * This stops, for large delegations, N*N lookups in the cache. */ +#define ITERATOR_NAME_CACHELOOKUP_MAX 3 +/* max number of lookups in the cache for parentside glue for nameserver names + * This stops, for larger delegations, N*N lookups in the cache. + * It is a little larger than the nonpside max, so it allows a couple extra + * lookups of parent side glue. */ +#define ITERATOR_NAME_CACHELOOKUP_MAX_PSIDE 5 + /** * Process config options and set iterator module state. * Sets default values if no config is found. diff --git a/iterator/iterator.c b/iterator/iterator.c index 25e5cfee..da9b7990 100644 --- a/iterator/iterator.c +++ b/iterator/iterator.c @@ -1218,6 +1218,15 @@ generate_dnskey_prefetch(struct module_qstate* qstate, (qstate->query_flags&BIT_RD) && !(qstate->query_flags&BIT_CD)){ return; } + /* we do not generate this prefetch when the query list is full, + * the query is fetched, if needed, when the validator wants it. + * At that time the validator waits for it, after spawning it. + * This means there is one state that uses cpu and a socket, the + * spawned while this one waits, and not several at the same time, + * if we had created the lookup here. And this helps to keep + * the total load down, but the query still succeeds to resolve. */ + if(mesh_jostle_exceeded(qstate->env->mesh)) + return; /* if the DNSKEY is in the cache this lookup will stop quickly */ log_nametypeclass(VERB_ALGO, "schedule dnskey prefetch", @@ -1911,6 +1920,14 @@ query_for_targets(struct module_qstate* qstate, struct iter_qstate* iq, return 0; } query_count++; + /* If the mesh query list is full, exit the loop here. + * This makes the routine spawn one query at a time, + * and this means there is no query state load + * increase, because the spawned state uses cpu and a + * socket while this state waits for that spawned + * state. Next time we can look up further targets */ + if(mesh_jostle_exceeded(qstate->env->mesh)) + break; } /* Send the A request. */ if(ie->supports_ipv4 && @@ -1925,6 +1942,9 @@ query_for_targets(struct module_qstate* qstate, struct iter_qstate* iq, return 0; } query_count++; + /* If the mesh query list is full, exit the loop. */ + if(mesh_jostle_exceeded(qstate->env->mesh)) + break; } /* mark this target as in progress. */ @@ -2085,6 +2105,15 @@ processLastResort(struct module_qstate* qstate, struct iter_qstate* iq, } ns->done_pside6 = 1; query_count++; + if(mesh_jostle_exceeded(qstate->env->mesh)) { + /* Wait for the lookup; do not spawn multiple + * lookups at a time. */ + verbose(VERB_ALGO, "try parent-side glue lookup"); + iq->num_target_queries += query_count; + target_count_increase(iq, query_count); + qstate->ext_state[id] = module_wait_subquery; + return 0; + } } if(ie->supports_ipv4 && !ns->done_pside4) { /* Send the A request. */ @@ -2560,7 +2589,12 @@ processQueryTargets(struct module_qstate* qstate, struct iter_qstate* iq, if(iq->depth < ie->max_dependency_depth && iq->num_target_queries == 0 && (!iq->target_count || iq->target_count[TARGET_COUNT_NX]==0) - && iq->sent_count < TARGET_FETCH_STOP) { + && iq->sent_count < TARGET_FETCH_STOP + /* if the mesh query list is full, then do not waste cpu + * and sockets to fetch promiscuous targets. They can be + * looked up when needed. */ + && !mesh_jostle_exceeded(qstate->env->mesh) + ) { tf_policy = ie->target_fetch_policy[iq->depth]; } diff --git a/services/cache/dns.c b/services/cache/dns.c index 6bca8d85..b6e56973 100644 --- a/services/cache/dns.c +++ b/services/cache/dns.c @@ -404,6 +404,9 @@ cache_fill_missing(struct module_env* env, uint16_t qclass, struct ub_packed_rrset_key* akey; time_t now = *env->now; for(ns = dp->nslist; ns; ns = ns->next) { + if(ns->cache_lookup_count > ITERATOR_NAME_CACHELOOKUP_MAX) + continue; + ns->cache_lookup_count++; akey = rrset_cache_lookup(env->rrset_cache, ns->name, ns->namelen, LDNS_RR_TYPE_A, qclass, 0, now, 0); if(akey) { diff --git a/services/mesh.c b/services/mesh.c index 30bcf7cd..2a411942 100644 --- a/services/mesh.c +++ b/services/mesh.c @@ -2240,3 +2240,10 @@ mesh_serve_expired_callback(void* arg) mesh_do_callback(mstate, LDNS_RCODE_NOERROR, msg->rep, c, &tv); } } + +int mesh_jostle_exceeded(struct mesh_area* mesh) +{ + if(mesh->all.count < mesh->max_reply_states) + return 0; + return 1; +} diff --git a/services/mesh.h b/services/mesh.h index 3be9b63f..25121a67 100644 --- a/services/mesh.h +++ b/services/mesh.h @@ -685,4 +685,15 @@ struct dns_msg* mesh_serve_expired_lookup(struct module_qstate* qstate, struct query_info* lookup_qinfo); +/** + * See if the mesh has space for more queries. You can allocate queries + * anyway, but this checks for the allocated space. + * @param mesh: mesh area. + * @return true if the query list is full. + * It checks the number of all queries, not just number of reply states, + * that have a client address. So that spawned queries count too, + * that were created by the iterator, or other modules. + */ +int mesh_jostle_exceeded(struct mesh_area* mesh); + #endif /* SERVICES_MESH_H */