-
Notifications
You must be signed in to change notification settings - Fork 979
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
DRILL-4706: Fragment planning causes Drillbits to read remote chunks …
…when local copies are available. New fragment placement algorithm based on locality of data.
- Loading branch information
Showing
14 changed files
with
965 additions
and
8 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
189 changes: 189 additions & 0 deletions
189
...c/main/java/org/apache/drill/exec/planner/fragment/LocalAffinityFragmentParallelizer.java
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,189 @@ | ||
| /** | ||
| * Licensed to the Apache Software Foundation (ASF) under one | ||
| * or more contributor license agreements. See the NOTICE file | ||
| * distributed with this work for additional information | ||
| * regarding copyright ownership. The ASF licenses this file | ||
| * to you 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 | ||
| * <p/> | ||
| * http://www.apache.org/licenses/LICENSE-2.0 | ||
| * <p/> | ||
| * 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 org.apache.drill.exec.planner.fragment; | ||
|
|
||
| import com.google.common.collect.Lists; | ||
| import com.google.common.collect.Ordering; | ||
| import org.apache.drill.exec.physical.EndpointAffinity; | ||
| import org.apache.drill.exec.physical.PhysicalOperatorSetupException; | ||
| import org.apache.drill.exec.proto.CoordinationProtos.DrillbitEndpoint; | ||
|
|
||
| import java.util.Map; | ||
| import java.util.List; | ||
| import java.util.Collection; | ||
| import java.util.HashMap; | ||
| import java.util.Collections; | ||
| import org.slf4j.Logger; | ||
|
|
||
| /** | ||
| * Implementation of {@link FragmentParallelizer} where fragment has zero or more endpoints. | ||
| * Fragment placement is done preferring data locality. | ||
| */ | ||
| public class LocalAffinityFragmentParallelizer implements FragmentParallelizer { | ||
| private static final Logger logger = org.slf4j.LoggerFactory.getLogger(LocalAffinityFragmentParallelizer.class); | ||
| public static final LocalAffinityFragmentParallelizer INSTANCE = new LocalAffinityFragmentParallelizer(); | ||
| private static String EOL = System.getProperty("line.separator"); | ||
|
|
||
| // Sort a list of map entries in decreasing order by values. | ||
| Ordering<Map.Entry<DrillbitEndpoint, Integer>> sortByValues = new Ordering<Map.Entry<DrillbitEndpoint, Integer>>() { | ||
| @Override | ||
| public int compare(Map.Entry<DrillbitEndpoint, Integer> left, Map.Entry<DrillbitEndpoint, Integer> right) { | ||
| return right.getValue().compareTo(left.getValue()); | ||
| } | ||
| }; | ||
|
|
||
| @Override | ||
| public void parallelizeFragment(final Wrapper fragmentWrapper, final ParallelizationParameters parameters, | ||
| final Collection<DrillbitEndpoint> activeEndpoints) throws PhysicalOperatorSetupException { | ||
| final Stats stats = fragmentWrapper.getStats(); | ||
| final ParallelizationInfo parallelizationInfo = stats.getParallelizationInfo(); | ||
| logger.trace("LocalAffinity Fragment Parallelizer: " + "MaxCost: {}, " + "SliceTarget: {}, " + | ||
| "Parallelization MaxWidth: {}," + EOL + "Parallelization MinWidth: {}," + "MaxGlobalWidth: {}," + | ||
| "MaxWidthPerNode {}," + EOL + "ActiveEndPoints: {}", | ||
| stats.getMaxCost(), parameters.getSliceTarget(), parallelizationInfo.getMaxWidth(), | ||
| parameters.getMaxGlobalWidth(), parameters.getMaxWidthPerNode(), activeEndpoints); | ||
|
|
||
| final Map<DrillbitEndpoint, EndpointAffinity> endpointAffinityMap = | ||
| fragmentWrapper.getStats().getParallelizationInfo().getEndpointAffinityMap(); | ||
| int totalLocalWorkUnits = 0; | ||
| Map<DrillbitEndpoint, Integer> localEndpointPool = new HashMap<>(); // Nodes with data locality. | ||
|
|
||
| // Get the total number of work units and list of endPoints with data locality to schedule fragments on | ||
| for (Map.Entry<DrillbitEndpoint, EndpointAffinity> epAff : endpointAffinityMap.entrySet()) { | ||
| if (epAff.getValue().getNumLocalWorkUnits() > 0) { | ||
| totalLocalWorkUnits += epAff.getValue().getNumLocalWorkUnits(); | ||
| localEndpointPool.put(epAff.getKey(), epAff.getValue().getNumLocalWorkUnits()); | ||
| } | ||
| } | ||
|
|
||
| // Find the parallelization width of fragment | ||
| // 1. Find the parallelization based on cost. Use max cost of all operators in this fragment; | ||
| int width = (int) Math.ceil(stats.getMaxCost() / parameters.getSliceTarget()); | ||
|
|
||
| // 2. Cap the parallelization width by fragment level width limit and system level per query width limit | ||
| width = Math.min(width, Math.min(parallelizationInfo.getMaxWidth(), parameters.getMaxGlobalWidth())); | ||
|
|
||
| // 3. Cap the parallelization width by system level per node width limit | ||
| width = Math.min(width, parameters.getMaxWidthPerNode() * activeEndpoints.size()); | ||
|
|
||
| // 4. Make sure width is at least the min width enforced by operators | ||
| width = Math.max(parallelizationInfo.getMinWidth(), width); | ||
|
|
||
| // 5. Make sure width is at most the max width enforced by operators | ||
| width = Math.min(parallelizationInfo.getMaxWidth(), width); | ||
|
|
||
| // 6: Finally make sure the width is at least one | ||
| width = Math.max(1, width); | ||
|
|
||
| List<DrillbitEndpoint> assignedEndPoints = Lists.newArrayList(); | ||
| int totalAssigned = 0; | ||
|
|
||
| // Sort the endpointPool based on numLocalWorkUnits. This sorting is done because we are doing | ||
| // round robin allocation and we stop when we reach the width. We want to allocate | ||
| // on endpoints which have higher numLocalWorkUnits first. | ||
| List<Map.Entry<DrillbitEndpoint, Integer>> sortedEndpointPool = Lists.newArrayList(localEndpointPool.entrySet()); | ||
| Collections.sort(sortedEndpointPool, sortByValues); | ||
|
|
||
| // Keep track of number of fragments allocated to each endpoint. | ||
| Map<DrillbitEndpoint, Integer> endpointAssignments = new HashMap<>(); | ||
|
|
||
| // Keep track of how many more to assign to each endpoint. | ||
| Map<DrillbitEndpoint, Integer> remainingEndpointAssignments = new HashMap<>(); | ||
|
|
||
| // localWidth is the width that we can allocate up to if we allocate only on nodes with locality. | ||
| int localWidth = Math.min(width, parameters.getMaxWidthPerNode() * localEndpointPool.size()); | ||
|
|
||
| logger.trace("LocalAffinity Fragment Parallelizer: " + "width: {}, " + "totalLocalworkUnits: {}, " + | ||
| "localWidth: {}," + EOL + "localEndpointPool: {}", | ||
| width, totalLocalWorkUnits, localWidth, localEndpointPool); | ||
|
|
||
| // Calculate the target allocation for each endPoint with data locality based on work it has to do | ||
| // Assign one fragment (minimum) to these endPoints. | ||
| for (DrillbitEndpoint ep : localEndpointPool.keySet()) { | ||
| final int numWorkUnits = endpointAffinityMap.get(ep).getNumLocalWorkUnits(); | ||
| final int targetAllocation = Math.min(numWorkUnits, | ||
| (int) Math.ceil(localWidth * ((double)numWorkUnits/totalLocalWorkUnits))); | ||
| assignedEndPoints.add(ep); | ||
| totalAssigned++; | ||
| endpointAssignments.put(ep, 1); | ||
| remainingEndpointAssignments.put(ep, targetAllocation - 1); | ||
| if (totalAssigned == localWidth) { // do not allocate more than local width | ||
| break; | ||
| } | ||
| } | ||
|
|
||
| // Keep allocating from endpoints in a round robin fashion up to min(targetAllocation, maxwidthPerNode) | ||
| // for each endpoint with data locality and upto localWidth all together. | ||
| while(totalAssigned < localWidth) { | ||
| int assignedThisRound = 0; | ||
| for (Map.Entry<DrillbitEndpoint, Integer> epEntry : sortedEndpointPool) { | ||
| DrillbitEndpoint ep = epEntry.getKey(); | ||
| final int remainingAssignments = remainingEndpointAssignments.get(ep); | ||
| final int currentAssignments = endpointAssignments.get(ep); | ||
| if (remainingAssignments > 0 && currentAssignments < parameters.getMaxWidthPerNode()) { | ||
| assignedEndPoints.add(ep); | ||
| remainingEndpointAssignments.put(ep, remainingAssignments - 1); | ||
| totalAssigned++; | ||
| assignedThisRound++; | ||
| endpointAssignments.put(ep, currentAssignments + 1); | ||
| } | ||
| if (totalAssigned == localWidth) { | ||
| break; | ||
| } | ||
| } | ||
| if (assignedThisRound == 0) { | ||
| break; | ||
| } | ||
| } | ||
| // At this point, we have taken care of allocating fragments for totalLocalWorkUnits, i.e. workUnits which | ||
| // have data locality information. | ||
| // For the workUnits which do not have data locality information (For the case where drillbits are not running | ||
| // on endPoints which have data and local filesystem), allocate them from the active endpoint pool. | ||
| // If we have already scheduled parallelizationInfo.getMaxWidth() fragments, do not schedule any more. | ||
| // Else, figure out fragments to schedule (how many and where ?) on active end points for unAssignedWorkUnits. | ||
| // We can assign max of upto width. | ||
| int unAssigned = parallelizationInfo.getMaxWidth() > totalLocalWorkUnits ? | ||
| (parallelizationInfo.getMaxWidth() - totalLocalWorkUnits) : 0; | ||
| while (totalAssigned < width && unAssigned > 0) { | ||
| for (DrillbitEndpoint ep : activeEndpoints) { | ||
| if (endpointAssignments.containsKey(ep) && | ||
| endpointAssignments.get(ep) >= parameters.getMaxWidthPerNode()) { | ||
| continue; | ||
| } | ||
| assignedEndPoints.add(ep); | ||
| totalAssigned++; | ||
| unAssigned--; | ||
| if (endpointAssignments.containsKey(ep)) { | ||
| endpointAssignments.put(ep, endpointAssignments.get(ep) + 1); | ||
| } else { | ||
| endpointAssignments.put(ep, 1); | ||
| } | ||
| if (unAssigned == 0 || totalAssigned == width) { | ||
| break; | ||
| } | ||
| } | ||
| } | ||
|
|
||
| logger.trace("LocalAffinity Fragment Parallelizer: " + "Total Assigned: {}" + EOL + | ||
| "Endpoint Assignments: {}", totalAssigned, endpointAssignments); | ||
|
|
||
| fragmentWrapper.setWidth(assignedEndPoints.size()); | ||
| fragmentWrapper.assignEndpoints(assignedEndPoints); | ||
| } | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Oops, something went wrong.