Skip to content

Use arrays to initialize the member variables of MultilevelSplitQueue #14139

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
hashhar merged 2 commits into from
Nov 1, 2022
Merged

Use arrays to initialize the member variables of MultilevelSplitQueue #14139

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
de3b7c2
Use arrays to initialize the member variables of MultilevelSplitQueue
tangjiangling Sep 15, 2022
52e148d
Rename variables for readability
tangjiangling Sep 15, 2022
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
54 changes: 25 additions & 29 deletions core/trino-main/src/main/java/io/trino/execution/executor/MultilevelSplitQueue.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -14,7 +14,6 @@
package io.trino.execution.executor;

import com.google.common.annotations.VisibleForTesting;
import com.google.common.collect.ImmutableList;
import io.airlift.stats.CounterStat;
import io.trino.execution.TaskManagerConfig;
import org.weakref.jmx.Managed;
Expand All @@ -24,9 +23,7 @@
import javax.annotation.concurrent.ThreadSafe;
import javax.inject.Inject;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.PriorityQueue;
import java.util.concurrent.atomic.AtomicLong;
import java.util.concurrent.locks.Condition;
Expand All @@ -44,12 +41,12 @@ public class MultilevelSplitQueue
static final long LEVEL_CONTRIBUTION_CAP = SECONDS.toNanos(30);

@GuardedBy("lock")
private final List<PriorityQueue<PrioritizedSplitRunner>> levelWaitingSplits;
private final PriorityQueue<PrioritizedSplitRunner>[] levelWaitingSplits;

private final AtomicLong[] levelScheduledTime = new AtomicLong[LEVEL_THRESHOLD_SECONDS.length];
private final AtomicLong[] levelScheduledTime;

private final AtomicLong[] levelMinPriority;
private final List<CounterStat> selectedLevelCounters;
private final CounterStat[] selectedLevelCounters;

private final ReentrantLock lock = new ReentrantLock();
private final Condition notEmpty = lock.newCondition();
Expand All @@ -64,18 +61,17 @@ public MultilevelSplitQueue(TaskManagerConfig taskManagerConfig)

public MultilevelSplitQueue(double levelTimeMultiplier)
{
this.levelScheduledTime = new AtomicLong[LEVEL_THRESHOLD_SECONDS.length];
this.levelMinPriority = new AtomicLong[LEVEL_THRESHOLD_SECONDS.length];
this.levelWaitingSplits = new ArrayList<>(LEVEL_THRESHOLD_SECONDS.length);
ImmutableList.Builder<CounterStat> counters = ImmutableList.builderWithExpectedSize(LEVEL_THRESHOLD_SECONDS.length);

for (int i = 0; i < LEVEL_THRESHOLD_SECONDS.length; i++) {
levelScheduledTime[i] = new AtomicLong();
levelMinPriority[i] = new AtomicLong(-1);
levelWaitingSplits.add(new PriorityQueue<>());
counters.add(new CounterStat());
}
this.levelWaitingSplits = new PriorityQueue[LEVEL_THRESHOLD_SECONDS.length];
this.selectedLevelCounters = new CounterStat[LEVEL_THRESHOLD_SECONDS.length];

this.selectedLevelCounters = counters.build();
for (int level = 0; level < LEVEL_THRESHOLD_SECONDS.length; level++) {
levelScheduledTime[level] = new AtomicLong();
levelMinPriority[level] = new AtomicLong(-1);
levelWaitingSplits[level] = new PriorityQueue<>();
selectedLevelCounters[level] = new CounterStat();
}

this.levelTimeMultiplier = levelTimeMultiplier;
}
Expand Down Expand Up @@ -103,7 +99,7 @@ public void offer(PrioritizedSplitRunner split)
int level = split.getPriority().getLevel();
lock.lock();
try {
if (levelWaitingSplits.get(level).isEmpty()) {
if (levelWaitingSplits[level].isEmpty()) {
// Accesses to levelScheduledTime are not synchronized, so we have a data race
// here - our level time math will be off. However, the staleness is bounded by
// the fact that only running splits that complete during this computation
Expand All @@ -114,7 +110,7 @@ public void offer(PrioritizedSplitRunner split)
levelScheduledTime[level].addAndGet(delta);
}

levelWaitingSplits.get(level).offer(split);
levelWaitingSplits[level].offer(split);
notEmpty.signal();
}
finally {
Expand All @@ -140,7 +136,7 @@ public PrioritizedSplitRunner take()

int selectedLevel = result.getPriority().getLevel();
levelMinPriority[selectedLevel].set(result.getPriority().getLevelPriority());
selectedLevelCounters.get(selectedLevel).update(1);
selectedLevelCounters[selectedLevel].update(1);

return result;
}
Expand All @@ -165,7 +161,7 @@ private PrioritizedSplitRunner pollSplit()
double worstRatio = 1;
int selectedLevel = -1;
for (int level = 0; level < LEVEL_THRESHOLD_SECONDS.length; level++) {
if (!levelWaitingSplits.get(level).isEmpty()) {
if (!levelWaitingSplits[level].isEmpty()) {
long levelTime = levelScheduledTime[level].get();
double ratio = levelTime == 0 ? 0 : targetScheduledTime / (1.0 * levelTime);
if (selectedLevel == -1 || ratio > worstRatio) {
Expand All @@ -181,7 +177,7 @@ private PrioritizedSplitRunner pollSplit()
return null;
}

PrioritizedSplitRunner result = levelWaitingSplits.get(selectedLevel).poll();
PrioritizedSplitRunner result = levelWaitingSplits[selectedLevel].poll();
checkState(result != null, "pollSplit cannot return null");

return result;
Expand Down Expand Up @@ -295,9 +291,9 @@ public int size()
public static int computeLevel(long threadUsageNanos)
{
long seconds = NANOSECONDS.toSeconds(threadUsageNanos);
for (int i = 0; i < (LEVEL_THRESHOLD_SECONDS.length - 1); i++) {
if (seconds < LEVEL_THRESHOLD_SECONDS[i + 1]) {
return i;
for (int level = 0; level < (LEVEL_THRESHOLD_SECONDS.length - 1); level++) {
if (seconds < LEVEL_THRESHOLD_SECONDS[level + 1]) {
return level;
}
}

Expand Down Expand Up @@ -344,34 +340,34 @@ public long getLevel4Time()
@Nested
public CounterStat getSelectedCountLevel0()
{
return selectedLevelCounters.get(0);
return selectedLevelCounters[0];
}

@Managed
@Nested
public CounterStat getSelectedCountLevel1()
{
return selectedLevelCounters.get(1);
return selectedLevelCounters[1];
}

@Managed
@Nested
public CounterStat getSelectedCountLevel2()
{
return selectedLevelCounters.get(2);
return selectedLevelCounters[2];
}

@Managed
@Nested
public CounterStat getSelectedCountLevel3()
{
return selectedLevelCounters.get(3);
return selectedLevelCounters[3];
}

@Managed
@Nested
public CounterStat getSelectedCountLevel4()
{
return selectedLevelCounters.get(4);
return selectedLevelCounters[4];
}
}