X-Git-Url: https://git.opendaylight.org/gerrit/gitweb?p=controller.git;a=blobdiff_plain;f=opendaylight%2Fmd-sal%2Fcds-access-client%2Fsrc%2Fmain%2Fjava%2Forg%2Fopendaylight%2Fcontroller%2Fcluster%2Faccess%2Fclient%2FAbstractClientConnection.java;h=380fdeb862bdb8fbb64b79cae0594803dd7fde7c;hp=47c0676979b94ea291532e5b713aee0bbcbece56;hb=715bf60ac1899a3c01690d244d26b12c9212ecc7;hpb=585e116247f9b616579ffad1785a972621d928e7 diff --git a/opendaylight/md-sal/cds-access-client/src/main/java/org/opendaylight/controller/cluster/access/client/AbstractClientConnection.java b/opendaylight/md-sal/cds-access-client/src/main/java/org/opendaylight/controller/cluster/access/client/AbstractClientConnection.java index 47c0676979..380fdeb862 100644 --- a/opendaylight/md-sal/cds-access-client/src/main/java/org/opendaylight/controller/cluster/access/client/AbstractClientConnection.java +++ b/opendaylight/md-sal/cds-access-client/src/main/java/org/opendaylight/controller/cluster/access/client/AbstractClientConnection.java @@ -13,9 +13,10 @@ import com.google.common.base.MoreObjects; import com.google.common.base.MoreObjects.ToStringHelper; import com.google.common.base.Preconditions; import edu.umd.cs.findbugs.annotations.SuppressFBWarnings; -import java.util.Iterator; +import java.util.Collection; import java.util.Optional; import java.util.concurrent.TimeUnit; +import java.util.concurrent.TimeoutException; import java.util.concurrent.locks.Lock; import java.util.concurrent.locks.ReentrantLock; import java.util.function.Consumer; @@ -26,6 +27,7 @@ import org.opendaylight.controller.cluster.access.concepts.Request; import org.opendaylight.controller.cluster.access.concepts.RequestException; import org.opendaylight.controller.cluster.access.concepts.Response; import org.opendaylight.controller.cluster.access.concepts.ResponseEnvelope; +import org.opendaylight.controller.cluster.access.concepts.RuntimeRequestException; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import scala.concurrent.duration.FiniteDuration; @@ -67,6 +69,13 @@ public abstract class AbstractClientConnection { @VisibleForTesting static final long NO_PROGRESS_TIMEOUT_NANOS = TimeUnit.MINUTES.toNanos(15); + // Emit a debug entry if we sleep for more that this amount + private static final long DEBUG_DELAY_NANOS = TimeUnit.MILLISECONDS.toNanos(100); + + // Upper bound on the time a thread is forced to sleep to keep queue size under control + private static final long MAX_DELAY_SECONDS = 5; + private static final long MAX_DELAY_NANOS = TimeUnit.SECONDS.toNanos(MAX_DELAY_SECONDS); + private final Lock lock = new ReentrantLock(); private final ClientActorContext context; @GuardedBy("lock") @@ -128,13 +137,7 @@ public abstract class AbstractClientConnection { */ public final void sendRequest(final Request request, final Consumer> callback) { final long now = currentTime(); - final long delay = enqueueEntry(new ConnectionEntry(request, callback, now), now); - try { - TimeUnit.NANOSECONDS.sleep(delay); - } catch (InterruptedException e) { - Thread.currentThread().interrupt(); - LOG.debug("Interrupted after sleeping {}ns", e, currentTime() - now); - } + sendEntry(new ConnectionEntry(request, callback, now), now); } /** @@ -154,57 +157,85 @@ public abstract class AbstractClientConnection { enqueueEntry(new ConnectionEntry(request, callback, enqueuedTicks), currentTime()); } + public final long enqueueEntry(final ConnectionEntry entry, final long now) { + lock.lock(); + try { + final RequestException maybePoison = poisoned; + if (maybePoison != null) { + throw new IllegalStateException("Connection " + this + " has been poisoned", maybePoison); + } + + if (queue.isEmpty()) { + // The queue is becoming non-empty, schedule a timer. + scheduleTimer(entry.getEnqueuedTicks() + REQUEST_TIMEOUT_NANOS - now); + } + return queue.enqueue(entry, now); + } finally { + lock.unlock(); + } + } + public abstract Optional getBackendInfo(); - final Iterable startReplay() { + final Collection startReplay() { lock.lock(); - return queue.asIterable(); + return queue.drain(); } @GuardedBy("lock") final void finishReplay(final ReconnectForwarder forwarder) { - queue.setForwarder(forwarder); + setForwarder(forwarder); + + /* + * The process of replaying all messages may have taken a significant chunk of time, depending on type + * of messages, queue depth and available processing power. In extreme situations this may have already + * exceeded BACKEND_ALIVE_TIMEOUT_NANOS, in which case we are running the risk of not making reasonable forward + * progress before we start a reconnect cycle. + * + * Note that the timer is armed after we have sent the first message, hence we should be seeing a response + * from the backend before we see a timeout, simply due to how the mailbox operates. + * + * At any rate, reset the timestamp once we complete reconnection (which an atomic transition from the + * perspective of outside world), as that makes it a bit easier to reason about timing of events. + */ + lastReceivedTicks = currentTime(); lock.unlock(); } @GuardedBy("lock") final void setForwarder(final ReconnectForwarder forwarder) { - final long now = currentTime(); - final Iterator it = queue.asIterable().iterator(); - while (it.hasNext()) { - final ConnectionEntry e = it.next(); - forwarder.forwardEntry(e, now); - it.remove(); - } - - queue.setForwarder(forwarder); + queue.setForwarder(forwarder, currentTime()); } @GuardedBy("lock") - abstract ClientActorBehavior lockedReconnect(ClientActorBehavior current); + abstract ClientActorBehavior lockedReconnect(ClientActorBehavior current, + RequestException runtimeRequestException); - final long enqueueEntry(final ConnectionEntry entry, final long now) { - lock.lock(); + final void sendEntry(final ConnectionEntry entry, final long now) { + long delay = enqueueEntry(entry, now); try { - final RequestException maybePoison = poisoned; - if (maybePoison != null) { - throw new IllegalStateException("Connection " + this + " has been poisoned", maybePoison); + if (delay >= DEBUG_DELAY_NANOS) { + if (delay > MAX_DELAY_NANOS) { + LOG.info("Capping {} throttle delay from {} to {} seconds", this, + TimeUnit.NANOSECONDS.toSeconds(delay), MAX_DELAY_SECONDS, new Throwable()); + delay = MAX_DELAY_NANOS; + } + if (LOG.isDebugEnabled()) { + LOG.debug("{}: Sleeping for {}ms on connection {}", context.persistenceId(), + TimeUnit.NANOSECONDS.toMillis(delay), this); + } } - - if (queue.isEmpty()) { - // The queue is becoming non-empty, schedule a timer. - scheduleTimer(entry.getEnqueuedTicks() + REQUEST_TIMEOUT_NANOS - now); - } - return queue.enqueue(entry, now); - } finally { - lock.unlock(); + TimeUnit.NANOSECONDS.sleep(delay); + } catch (InterruptedException e) { + Thread.currentThread().interrupt(); + LOG.debug("Interrupted after sleeping {}ns", e, currentTime() - now); } } - final ClientActorBehavior reconnect(final ClientActorBehavior current) { + final ClientActorBehavior reconnect(final ClientActorBehavior current, final RequestException cause) { lock.lock(); try { - return lockedReconnect(current); + return lockedReconnect(current, cause); } finally { lock.unlock(); } @@ -218,11 +249,11 @@ public abstract class AbstractClientConnection { @GuardedBy("lock") private void scheduleTimer(final long delay) { if (haveTimer) { - LOG.debug("{}: timer already scheduled", context.persistenceId()); + LOG.debug("{}: timer already scheduled on {}", context.persistenceId(), this); return; } if (queue.hasSuccessor()) { - LOG.debug("{}: connection has successor, not scheduling timer", context.persistenceId()); + LOG.debug("{}: connection {} has a successor, not scheduling timer", context.persistenceId(), this); return; } @@ -231,7 +262,7 @@ public abstract class AbstractClientConnection { final long normalized = delay <= 0 ? 0 : Math.min(delay, BACKEND_ALIVE_TIMEOUT_NANOS); final FiniteDuration dur = FiniteDuration.fromNanos(normalized); - LOG.debug("{}: scheduling timeout in {}", context.persistenceId(), dur); + LOG.debug("{}: connection {} scheduling timeout in {}", context.persistenceId(), this, dur); context.executeInActor(this::runTimer, dur); haveTimer = true; } @@ -251,6 +282,9 @@ public abstract class AbstractClientConnection { try { haveTimer = false; final long now = currentTime(); + + LOG.debug("{}: running timer on {}", context.persistenceId(), this); + // The following line is only reliable when queue is not forwarding, but such state should not last long. // FIXME: BUG-8422: this may not be accurate w.r.t. replayed entries final long ticksSinceProgress = queue.ticksStalling(now); @@ -269,12 +303,16 @@ public abstract class AbstractClientConnection { delay = lockedCheckTimeout(now); if (delay == null) { // We have timed out. There is no point in scheduling a timer - return lockedReconnect(current); + LOG.debug("{}: connection {} timed out", context.persistenceId(), this); + return lockedReconnect(current, new RuntimeRequestException("Backend connection timed out", + new TimeoutException())); } if (delay.isPresent()) { // If there is new delay, schedule a timer scheduleTimer(delay.get()); + } else { + LOG.debug("{}: not scheduling timeout on {}", context.persistenceId(), this); } } finally { lock.unlock(); @@ -293,6 +331,10 @@ public abstract class AbstractClientConnection { } } + long backendSilentTicks(final long now) { + return now - lastReceivedTicks; + } + /* * We are using tri-state return here to indicate one of three conditions: * - if there is no timeout to schedule, return Optional.empty() @@ -304,13 +346,14 @@ public abstract class AbstractClientConnection { @GuardedBy("lock") private Optional lockedCheckTimeout(final long now) { if (queue.isEmpty()) { + LOG.debug("{}: connection {} is empty", context.persistenceId(), this); return Optional.empty(); } - final long backendSilentTicks = now - lastReceivedTicks; + final long backendSilentTicks = backendSilentTicks(now); if (backendSilentTicks >= BACKEND_ALIVE_TIMEOUT_NANOS) { - LOG.debug("Connection {} has not seen activity from backend for {} nanoseconds, timing out", this, - backendSilentTicks); + LOG.debug("{}: Connection {} has not seen activity from backend for {} nanoseconds, timing out", + context.persistenceId(), this, backendSilentTicks); return null; } @@ -323,9 +366,11 @@ public abstract class AbstractClientConnection { tasksTimedOut++; queue.remove(now); - LOG.debug("Connection {} timed out entryt {}", this, head); + LOG.debug("{}: Connection {} timed out entry {}", context.persistenceId(), this, head); + + final double time = (beenOpen * 1.0) / 1_000_000_000; head.complete(head.getRequest().toRequestFailure( - new RequestTimeoutException("Timed out after " + beenOpen + "ns"))); + new RequestTimeoutException("Timed out after " + time + "seconds"))); } LOG.debug("Connection {} timed out {} tasks", this, tasksTimedOut); @@ -347,10 +392,14 @@ public abstract class AbstractClientConnection { @GuardedBy("lock") private void lockedPoison(final RequestException cause) { - poisoned = cause; + poisoned = enrichPoison(cause); queue.poison(cause); } + RequestException enrichPoison(final RequestException ex) { + return ex; + } + @VisibleForTesting final RequestException poisoned() { return poisoned;