UDP per select speedup.

git-svn-id: file:///svn/unbound/trunk@968 be551aaa-1e26-0410-a405-d3ace91eadb9

diff --git a/doc/Changelog b/doc/Changelog
index e97c24769c495a965a996e71ba582ca89e91cdbc..05c89517e27155b6a8c86a7b10b79c63b25e18f5 100644 (file)
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -7,6 +7,9 @@
        - mini_event shares the time value with unbound this results in 
          +3% speed for cache responses and +9% for recursions.
        - ldns tarball update with new NSEC3 sign code numbers.
+       - perform several reads per UDP operation. This improves performance
+         in DoS conditions, and costs very little in normal conditions.
+         improves cache response +50%, and recursions +10%.
 
 18 February 2008: Wouter
        - patch to unbound-host from Jan-Piet Mens.

diff --git a/util/netevent.c b/util/netevent.c
index 0b7995f1e87e1eea9426d7f61b432228b75d6a3b..e1f6e60034eb7fd8154c43aa03079df71ad5fd1a 100644 (file)
--- a/util/netevent.c
+++ b/util/netevent.c
@@ -48,6 +48,9 @@
 /** The TCP reading or writing query timeout in seconds */
 #define TCP_QUERY_TIMEOUT 120 
 
+/** number of UDP reads to perform per read indication from select */
+#define NUM_UDP_PER_SELECT 100
+
 /* We define libevent structures here to hide the libevent stuff. */
 
 #ifdef USE_MINI_EVENT
@@ -110,6 +113,7 @@ static struct comm_point* comm_point_create_tcp_handler(
 /* -------- End of local definitions -------- */
 
 #ifdef USE_MINI_EVENT
+/** minievent updates the time when it blocks. */
 #define comm_base_now(x) /* nothing to do */
 #else /* !USE_MINI_EVENT */
 /** fillup the time values in the event base */
@@ -360,6 +364,7 @@ comm_point_udp_ancil_callback(int fd, short event, void* arg)
        struct iovec iov[1];
        ssize_t recv;
        char ancil[256];
+       int i;
 #ifndef S_SPLINT_S
        struct cmsghdr* cmsg;
 #endif /* S_SPLINT_S */
@@ -371,66 +376,68 @@ comm_point_udp_ancil_callback(int fd, short event, void* arg)
                return;
        log_assert(rep.c && rep.c->buffer && rep.c->fd == fd);
        comm_base_now(rep.c->ev->base);
-       ldns_buffer_clear(rep.c->buffer);
-       rep.addrlen = (socklen_t)sizeof(rep.addr);
-       log_assert(fd != -1);
-       log_assert(ldns_buffer_remaining(rep.c->buffer) > 0);
-       msg.msg_name = &rep.addr;
-       msg.msg_namelen = (socklen_t)sizeof(rep.addr);
-       iov[0].iov_base = ldns_buffer_begin(rep.c->buffer);
-       iov[0].iov_len = ldns_buffer_remaining(rep.c->buffer);
-       msg.msg_iov = iov;
-       msg.msg_iovlen = 1;
-       msg.msg_control = ancil;
+       for(i=0; i<NUM_UDP_PER_SELECT; i++) {
+               ldns_buffer_clear(rep.c->buffer);
+               rep.addrlen = (socklen_t)sizeof(rep.addr);
+               log_assert(fd != -1);
+               log_assert(ldns_buffer_remaining(rep.c->buffer) > 0);
+               msg.msg_name = &rep.addr;
+               msg.msg_namelen = (socklen_t)sizeof(rep.addr);
+               iov[0].iov_base = ldns_buffer_begin(rep.c->buffer);
+               iov[0].iov_len = ldns_buffer_remaining(rep.c->buffer);
+               msg.msg_iov = iov;
+               msg.msg_iovlen = 1;
+               msg.msg_control = ancil;
 #ifndef S_SPLINT_S
-       msg.msg_controllen = sizeof(ancil);
+               msg.msg_controllen = sizeof(ancil);
 #endif /* S_SPLINT_S */
-       msg.msg_flags = 0;
-       recv = recvmsg(fd, &msg, 0);
-       if(recv == -1) {
-               if(errno != EAGAIN && errno != EINTR) {
-                       log_err("recvmsg failed: %s", strerror(errno));
+               msg.msg_flags = 0;
+               recv = recvmsg(fd, &msg, 0);
+               if(recv == -1) {
+                       if(errno != EAGAIN && errno != EINTR) {
+                               log_err("recvmsg failed: %s", strerror(errno));
+                       }
+                       return;
                }
-               return;
-       }
-       rep.addrlen = msg.msg_namelen;
-       ldns_buffer_skip(rep.c->buffer, recv);
-       ldns_buffer_flip(rep.c->buffer);
-       rep.srctype = 0;
+               rep.addrlen = msg.msg_namelen;
+               ldns_buffer_skip(rep.c->buffer, recv);
+               ldns_buffer_flip(rep.c->buffer);
+               rep.srctype = 0;
 #ifndef S_SPLINT_S
-       for(cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
-               cmsg = CMSG_NXTHDR(&msg, cmsg)) {
-               if( cmsg->cmsg_level == IPPROTO_IPV6 &&
-                       cmsg->cmsg_type == IPV6_PKTINFO) {
-                       rep.srctype = 6;
-                       memmove(&rep.pktinfo.v6info, CMSG_DATA(cmsg),
-                               sizeof(struct in6_pktinfo));
-                       break;
+               for(cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
+                       cmsg = CMSG_NXTHDR(&msg, cmsg)) {
+                       if( cmsg->cmsg_level == IPPROTO_IPV6 &&
+                               cmsg->cmsg_type == IPV6_PKTINFO) {
+                               rep.srctype = 6;
+                               memmove(&rep.pktinfo.v6info, CMSG_DATA(cmsg),
+                                       sizeof(struct in6_pktinfo));
+                               break;
 #ifdef IP_RECVDSTADDR
-               } else if( cmsg->cmsg_level == IPPROTO_IP &&
-                       cmsg->cmsg_type == IP_RECVDSTADDR) {
-                       rep.srctype = 4;
-                       memmove(&rep.pktinfo.v4addr, CMSG_DATA(cmsg),
-                               sizeof(struct in_addr));
-                       break;
+                       } else if( cmsg->cmsg_level == IPPROTO_IP &&
+                               cmsg->cmsg_type == IP_RECVDSTADDR) {
+                               rep.srctype = 4;
+                               memmove(&rep.pktinfo.v4addr, CMSG_DATA(cmsg),
+                                       sizeof(struct in_addr));
+                               break;
 #elif defined(IP_PKTINFO)
-               } else if( cmsg->cmsg_level == IPPROTO_IP &&
-                       cmsg->cmsg_type == IP_PKTINFO) {
-                       rep.srctype = 4;
-                       memmove(&rep.pktinfo.v4info, CMSG_DATA(cmsg),
-                               sizeof(struct in_pktinfo));
-                       break;
+                       } else if( cmsg->cmsg_level == IPPROTO_IP &&
+                               cmsg->cmsg_type == IP_PKTINFO) {
+                               rep.srctype = 4;
+                               memmove(&rep.pktinfo.v4info, CMSG_DATA(cmsg),
+                                       sizeof(struct in_pktinfo));
+                               break;
 #endif
+                       }
                }
-       }
-       if(verbosity >= VERB_ALGO)
-               p_ancil("receive_udp on interface", &rep);
+               if(verbosity >= VERB_ALGO)
+                       p_ancil("receive_udp on interface", &rep);
 #endif /* S_SPLINT_S */
-       log_assert(fptr_whitelist_comm_point(rep.c->callback));
-       if((*rep.c->callback)(rep.c, rep.c->cb_arg, NETEVENT_NOERROR, &rep)) {
-               /* send back immediate reply */
-               (void)comm_point_send_udp_msg_if(rep.c, rep.c->buffer,
-                       (struct sockaddr*)&rep.addr, rep.addrlen, &rep);
+               log_assert(fptr_whitelist_comm_point(rep.c->callback));
+               if((*rep.c->callback)(rep.c, rep.c->cb_arg, NETEVENT_NOERROR, &rep)) {
+                       /* send back immediate reply */
+                       (void)comm_point_send_udp_msg_if(rep.c, rep.c->buffer,
+                               (struct sockaddr*)&rep.addr, rep.addrlen, &rep);
+               }
        }
 #else
        fatal_exit("recvmsg: No support for IPV6_PKTINFO. "
@@ -443,6 +450,7 @@ comm_point_udp_callback(int fd, short event, void* arg)
 {
        struct comm_reply rep;
        ssize_t recv;
+       int i;
 
        rep.c = (struct comm_point*)arg;
        log_assert(rep.c->type == comm_udp);
@@ -451,27 +459,29 @@ comm_point_udp_callback(int fd, short event, void* arg)
                return;
        log_assert(rep.c && rep.c->buffer && rep.c->fd == fd);
        comm_base_now(rep.c->ev->base);
-       ldns_buffer_clear(rep.c->buffer);
-       rep.addrlen = (socklen_t)sizeof(rep.addr);
-       log_assert(fd != -1);
-       log_assert(ldns_buffer_remaining(rep.c->buffer) > 0);
-       recv = recvfrom(fd, ldns_buffer_begin(rep.c->buffer), 
-               ldns_buffer_remaining(rep.c->buffer), 0, 
-               (struct sockaddr*)&rep.addr, &rep.addrlen);
-       if(recv == -1) {
-               if(errno != EAGAIN && errno != EINTR) {
-                       log_err("recvfrom failed: %s", strerror(errno));
+       for(i=0; i<NUM_UDP_PER_SELECT; i++) {
+               ldns_buffer_clear(rep.c->buffer);
+               rep.addrlen = (socklen_t)sizeof(rep.addr);
+               log_assert(fd != -1);
+               log_assert(ldns_buffer_remaining(rep.c->buffer) > 0);
+               recv = recvfrom(fd, ldns_buffer_begin(rep.c->buffer), 
+                       ldns_buffer_remaining(rep.c->buffer), 0, 
+                       (struct sockaddr*)&rep.addr, &rep.addrlen);
+               if(recv == -1) {
+                       if(errno != EAGAIN && errno != EINTR) {
+                               log_err("recvfrom failed: %s", strerror(errno));
+                       }
+                       return;
+               }
+               ldns_buffer_skip(rep.c->buffer, recv);
+               ldns_buffer_flip(rep.c->buffer);
+               rep.srctype = 0;
+               log_assert(fptr_whitelist_comm_point(rep.c->callback));
+               if((*rep.c->callback)(rep.c, rep.c->cb_arg, NETEVENT_NOERROR, &rep)) {
+                       /* send back immediate reply */
+                       (void)comm_point_send_udp_msg(rep.c, rep.c->buffer,
+                               (struct sockaddr*)&rep.addr, rep.addrlen);
                }
-               return;
-       }
-       ldns_buffer_skip(rep.c->buffer, recv);
-       ldns_buffer_flip(rep.c->buffer);
-       rep.srctype = 0;
-       log_assert(fptr_whitelist_comm_point(rep.c->callback));
-       if((*rep.c->callback)(rep.c, rep.c->cb_arg, NETEVENT_NOERROR, &rep)) {
-               /* send back immediate reply */
-               (void)comm_point_send_udp_msg(rep.c, rep.c->buffer,
-                       (struct sockaddr*)&rep.addr, rep.addrlen);
        }
 }