/*
* Copyright 2010 LinkedIn, Inc
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package voldemort.store.routed.action;
import java.util.List;
import java.util.Map;
import voldemort.cluster.Node;
import voldemort.cluster.failuredetector.FailureDetector;
import voldemort.store.InsufficientOperationalNodesException;
import voldemort.store.InsufficientZoneResponsesException;
import voldemort.store.Store;
import voldemort.store.StoreRequest;
import voldemort.store.routed.BasicPipelineData;
import voldemort.store.routed.Pipeline;
import voldemort.store.routed.Pipeline.Event;
import voldemort.store.routed.Response;
import voldemort.utils.ByteArray;
import voldemort.utils.ByteUtils;
import voldemort.utils.Time;
public class PerformSerialRequests<V, PD extends BasicPipelineData<V>> extends
AbstractKeyBasedAction<ByteArray, V, PD> {
private final FailureDetector failureDetector;
private final Map<Integer, Store<ByteArray, byte[], byte[]>> stores;
private final int preferred;
private final int required;
private final StoreRequest<V> storeRequest;
private final Event insufficientSuccessesEvent;
public PerformSerialRequests(PD pipelineData,
Event completeEvent,
ByteArray key,
FailureDetector failureDetector,
Map<Integer, Store<ByteArray, byte[], byte[]>> stores,
int preferred,
int required,
StoreRequest<V> storeRequest,
Event insufficientSuccessesEvent) {
super(pipelineData, completeEvent, key);
this.failureDetector = failureDetector;
this.stores = stores;
this.preferred = preferred;
this.required = required;
this.storeRequest = storeRequest;
this.insufficientSuccessesEvent = insufficientSuccessesEvent;
}
/**
* Checks whether every property except 'preferred' is satisfied
*
* @return
*/
private boolean isSatisfied() {
if(pipelineData.getZonesRequired() != null) {
return ((pipelineData.getSuccesses() >= required) && (pipelineData.getZoneResponses()
.size() >= (pipelineData.getZonesRequired() + 1)));
} else {
return pipelineData.getSuccesses() >= required;
}
}
public void execute(Pipeline pipeline) {
List<Node> nodes = pipelineData.getNodes();
// Now if we had any failures we will be short a few reads. Do serial
// reads to make up for these.
while(pipelineData.getSuccesses() < preferred && pipelineData.getNodeIndex() < nodes.size()) {
Node node = nodes.get(pipelineData.getNodeIndex());
long start = System.nanoTime();
try {
Store<ByteArray, byte[], byte[]> store = stores.get(node.getId());
V result = storeRequest.request(store);
Response<ByteArray, V> response = new Response<ByteArray, V>(node,
key,
result,
((System.nanoTime() - start) / Time.NS_PER_MS));
if(logger.isDebugEnabled())
logger.debug(pipeline.getOperation().getSimpleName() + " for key "
+ ByteUtils.toHexString(key.get()) + " successes: "
+ pipelineData.getSuccesses() + " preferred: " + preferred
+ " required: " + required + " new "
+ pipeline.getOperation().getSimpleName() + " success on node "
+ node.getId());
pipelineData.incrementSuccesses();
pipelineData.getResponses().add(response);
failureDetector.recordSuccess(response.getNode(), response.getRequestTime());
pipelineData.getZoneResponses().add(node.getZoneId());
} catch(Exception e) {
long requestTime = (System.nanoTime() - start) / Time.NS_PER_MS;
if(handleResponseError(e, node, requestTime, pipeline, failureDetector))
return;
}
// break out if we have satisfied everything
if(isSatisfied())
break;
pipelineData.incrementNodeIndex();
}
if(pipelineData.getSuccesses() < required) {
if(insufficientSuccessesEvent != null) {
pipeline.addEvent(insufficientSuccessesEvent);
} else {
pipelineData.setFatalError(new InsufficientOperationalNodesException(required
+ " "
+ pipeline.getOperation()
.getSimpleName()
+ "s required, but only "
+ pipelineData.getSuccesses()
+ " succeeded",
pipelineData.getReplicationSet(),
pipelineData.getNodes(),
pipelineData.getFailedNodes(),
pipelineData.getFailures()));
pipeline.abort();
}
} else {
if(pipelineData.getZonesRequired() != null) {
int zonesSatisfied = pipelineData.getZoneResponses().size();
if(zonesSatisfied >= (pipelineData.getZonesRequired() + 1)) {
pipeline.addEvent(completeEvent);
} else {
// if you run with zoneCountReads > 0, we could frequently
// run into this exception since our preference list for
// zone routing is laid out thus : <a node from each of
// 'zoneCountReads' zones>, <nodes from local zone>, <nodes
// from remote zone1>, <nodes from remote zone2>,...
// #preferred number of reads may not be able to satisfy
// zoneCountReads, if the original read to a remote node
// fails in the parallel stage
pipelineData.setFatalError(new InsufficientZoneResponsesException((pipelineData.getZonesRequired() + 1)
+ " "
+ pipeline.getOperation()
.getSimpleName()
+ "s required zone, but only "
+ zonesSatisfied
+ " succeeded"));
pipeline.abort();
}
} else {
pipeline.addEvent(completeEvent);
}
}
}
}