HBASE-12148 Remove TimeRangeTracker as point of contention when many threads writing a Store (Huaxiang Sun)

This commit is contained in:
Michael Stack 2017-01-09 13:24:53 -08:00
parent 1576269123
commit dd1ae37148
3 changed files with 154 additions and 54 deletions

View File

@ -313,8 +313,7 @@ public class ClassSize {
TIMERANGE = align(ClassSize.OBJECT + Bytes.SIZEOF_LONG * 2 + Bytes.SIZEOF_BOOLEAN);
TIMERANGE_TRACKER = align(ClassSize.OBJECT + Bytes.SIZEOF_LONG * 2);
TIMERANGE_TRACKER = align(ClassSize.OBJECT + 2 * REFERENCE);
CELL_SET = align(OBJECT + REFERENCE);
STORE_SERVICES = align(OBJECT + REFERENCE + ATOMIC_LONG);

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@ -21,6 +21,7 @@ package org.apache.hadoop.hbase.regionserver;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.concurrent.atomic.AtomicLong;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.CellUtil;
@ -28,9 +29,9 @@ import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.io.TimeRange;
import org.apache.hadoop.hbase.util.Writables;
import org.apache.hadoop.io.Writable;
/**
* Stores minimum and maximum timestamp values.
* Stores minimum and maximum timestamp values, it is [minimumTimestamp, maximumTimestamp] in
* interval notation.
* Use this class at write-time ONLY. Too much synchronization to use at read time
* (TODO: there are two scenarios writing, once when lots of concurrency as part of memstore
* updates but then later we can make one as part of a compaction when there is only one thread
@ -46,8 +47,9 @@ import org.apache.hadoop.io.Writable;
public class TimeRangeTracker implements Writable {
static final long INITIAL_MIN_TIMESTAMP = Long.MAX_VALUE;
static final long INITIAL_MAX_TIMESTAMP = -1L;
long minimumTimestamp = INITIAL_MIN_TIMESTAMP;
long maximumTimestamp = INITIAL_MAX_TIMESTAMP;
AtomicLong minimumTimestamp = new AtomicLong(INITIAL_MIN_TIMESTAMP);
AtomicLong maximumTimestamp = new AtomicLong(INITIAL_MAX_TIMESTAMP);
/**
* Default constructor.
@ -60,26 +62,13 @@ public class TimeRangeTracker implements Writable {
* @param trt source TimeRangeTracker
*/
public TimeRangeTracker(final TimeRangeTracker trt) {
set(trt.getMin(), trt.getMax());
minimumTimestamp.set(trt.getMin());
maximumTimestamp.set(trt.getMax());
}
public TimeRangeTracker(long minimumTimestamp, long maximumTimestamp) {
set(minimumTimestamp, maximumTimestamp);
}
private void set(final long min, final long max) {
this.minimumTimestamp = min;
this.maximumTimestamp = max;
}
/**
* @param l
* @return True if we initialized values
*/
private boolean init(final long l) {
if (this.minimumTimestamp != INITIAL_MIN_TIMESTAMP) return false;
set(l, l);
return true;
this.minimumTimestamp.set(minimumTimestamp);
this.maximumTimestamp.set(maximumTimestamp);
}
/**
@ -102,23 +91,44 @@ public class TimeRangeTracker implements Writable {
@edu.umd.cs.findbugs.annotations.SuppressWarnings(value="MT_CORRECTNESS",
justification="Intentional")
void includeTimestamp(final long timestamp) {
// Do test outside of synchronization block. Synchronization in here can be problematic
// when many threads writing one Store -- they can all pile up trying to add in here.
// Happens when doing big write upload where we are hammering on one region.
if (timestamp < this.minimumTimestamp) {
synchronized (this) {
if (!init(timestamp)) {
if (timestamp < this.minimumTimestamp) {
this.minimumTimestamp = timestamp;
}
long initialMinTimestamp = this.minimumTimestamp.get();
if (timestamp < initialMinTimestamp) {
long curMinTimestamp = initialMinTimestamp;
while (timestamp < curMinTimestamp) {
if (!this.minimumTimestamp.compareAndSet(curMinTimestamp, timestamp)) {
curMinTimestamp = this.minimumTimestamp.get();
} else {
// successfully set minimumTimestamp, break.
break;
}
}
} else if (timestamp > this.maximumTimestamp) {
synchronized (this) {
if (!init(timestamp)) {
if (this.maximumTimestamp < timestamp) {
this.maximumTimestamp = timestamp;
}
// When it reaches here, there are two possibilities:
// 1). timestamp >= curMinTimestamp, someone already sets the minimumTimestamp. In this case,
// it still needs to check if initialMinTimestamp == INITIAL_MIN_TIMESTAMP to see
// if it needs to update minimumTimestamp. Someone may already set both
// minimumTimestamp/minimumTimestamp to the same value(curMinTimestamp),
// need to check if maximumTimestamp needs to be updated.
// 2). timestamp < curMinTimestamp, it sets the minimumTimestamp successfully.
// In this case,it still needs to check if initialMinTimestamp == INITIAL_MIN_TIMESTAMP
// to see if it needs to set maximumTimestamp.
if (initialMinTimestamp != INITIAL_MIN_TIMESTAMP) {
// Someone already sets minimumTimestamp and timestamp is less than minimumTimestamp.
// In this case, no need to set maximumTimestamp as it will be set to at least
// initialMinTimestamp.
return;
}
}
long curMaxTimestamp = this.maximumTimestamp.get();
if (timestamp > curMaxTimestamp) {
while (timestamp > curMaxTimestamp) {
if (!this.maximumTimestamp.compareAndSet(curMaxTimestamp, timestamp)) {
curMaxTimestamp = this.maximumTimestamp.get();
} else {
// successfully set maximumTimestamp, break
break;
}
}
}
@ -126,40 +136,41 @@ public class TimeRangeTracker implements Writable {
/**
* Check if the range has ANY overlap with TimeRange
* @param tr TimeRange
* @param tr TimeRange, it expects [minStamp, maxStamp)
* @return True if there is overlap, false otherwise
*/
public synchronized boolean includesTimeRange(final TimeRange tr) {
return (this.minimumTimestamp < tr.getMax() && this.maximumTimestamp >= tr.getMin());
public boolean includesTimeRange(final TimeRange tr) {
return (this.minimumTimestamp.get() < tr.getMax() && this.maximumTimestamp.get() >= tr.getMin());
}
/**
* @return the minimumTimestamp
*/
public synchronized long getMin() {
return minimumTimestamp;
public long getMin() {
return minimumTimestamp.get();
}
/**
* @return the maximumTimestamp
*/
public synchronized long getMax() {
return maximumTimestamp;
public long getMax() {
return maximumTimestamp.get();
}
public synchronized void write(final DataOutput out) throws IOException {
out.writeLong(minimumTimestamp);
out.writeLong(maximumTimestamp);
public void write(final DataOutput out) throws IOException {
out.writeLong(minimumTimestamp.get());
out.writeLong(maximumTimestamp.get());
}
public synchronized void readFields(final DataInput in) throws IOException {
this.minimumTimestamp = in.readLong();
this.maximumTimestamp = in.readLong();
public void readFields(final DataInput in) throws IOException {
this.minimumTimestamp.set(in.readLong());
this.maximumTimestamp.set(in.readLong());
}
@Override
public synchronized String toString() {
return "[" + minimumTimestamp + "," + maximumTimestamp + "]";
public String toString() {
return "[" + minimumTimestamp.get() + "," + maximumTimestamp.get() + "]";
}
/**

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@ -29,10 +29,12 @@ import org.apache.hadoop.hbase.testclassification.RegionServerTests;
import org.junit.Test;
import org.junit.experimental.categories.Category;
import java.io.IOException;
import java.util.concurrent.ThreadLocalRandom;
@Category({RegionServerTests.class, SmallTests.class})
public class TestTimeRangeTracker {
private static final int NUM_KEYS = 10000000;
@Test
public void testExtreme() {
TimeRange tr = new TimeRange();
@ -119,6 +121,7 @@ public class TestTimeRangeTracker {
for (int i = 0; i < threads.length; i++) {
threads[i].join();
}
assertTrue(trr.getMax() == calls * threadCount);
assertTrue(trr.getMin() == 0);
}
@ -156,6 +159,93 @@ public class TestTimeRangeTracker {
assertFalse(twoArgRange3.isAllTime());
}
final static int NUM_OF_THREADS = 20;
class RandomTestData {
private long[] keys = new long[NUM_KEYS];
private long min = Long.MAX_VALUE;
private long max = 0;
public RandomTestData() {
if (ThreadLocalRandom.current().nextInt(NUM_OF_THREADS) % 2 == 0) {
for (int i = 0; i < NUM_KEYS; i++) {
keys[i] = i + ThreadLocalRandom.current().nextLong(NUM_OF_THREADS);
if (keys[i] < min) min = keys[i];
if (keys[i] > max) max = keys[i];
}
} else {
for (int i = NUM_KEYS - 1; i >= 0; i--) {
keys[i] = i + ThreadLocalRandom.current().nextLong(NUM_OF_THREADS);
if (keys[i] < min) min = keys[i];
if (keys[i] > max) max = keys[i];
}
}
}
public long getMax() {
return this.max;
}
public long getMin() {
return this.min;
}
}
class TrtUpdateRunnable implements Runnable {
private TimeRangeTracker trt;
private RandomTestData data;
public TrtUpdateRunnable(final TimeRangeTracker trt, final RandomTestData data) {
this.trt = trt;
this.data = data;
}
public void run() {
for (long key : data.keys) {
trt.includeTimestamp(key);
}
}
}
/**
* Run a bunch of threads against a single TimeRangeTracker and ensure we arrive
* at right range. The data chosen is going to ensure that there are lots collisions, i.e,
* some other threads may already update the value while one tries to update min/max value.
*/
@Test
public void testConcurrentIncludeTimestampCorrectness() {
RandomTestData[] testData = new RandomTestData[NUM_OF_THREADS];
long min = Long.MAX_VALUE, max = 0;
for (int i = 0; i < NUM_OF_THREADS; i ++) {
testData[i] = new RandomTestData();
if (testData[i].getMin() < min) {
min = testData[i].getMin();
}
if (testData[i].getMax() > max) {
max = testData[i].getMax();
}
}
TimeRangeTracker trt = new TimeRangeTracker();
Thread[] t = new Thread[NUM_OF_THREADS];
for (int i = 0; i < NUM_OF_THREADS; i++) {
t[i] = new Thread(new TrtUpdateRunnable(trt, testData[i]));
t[i].start();
}
for (Thread thread : t) {
try {
thread.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
assertTrue(min == trt.getMin());
assertTrue(max == trt.getMax());
}
/**
* Bit of code to test concurrent access on this class.
* @param args